New Inch & Mil-Spec Precision Shoulder Screws

MF Supply is happy to announce that in addition to our Metric Precision Shoulder Screw line, we are now offering Inch and Mil-Spec Precision Shoulder Screws, including MS51575 & MS51576. These new products are available for RFQ directly from!

As your source for functional equivalents to expensive brand name fasteners, we know how to save you money and reduce long lead times commonly found with brand name fasteners.

Here is an example of a functional equivalent in action:

The following screw, available for RFQ at, has a generic description as follows:
3/16” shoulder diameter x 1” long x 8-32 thread in SS18-8 (300 Series) with a hex-socket drive. Below we list seven OEM brands (yes, seven!) including their part numbers, and one Mil-Spec part number that are all functional equivalents:

    • Grainger 6JY20
    • Lyn-tron SS7431-00
    • McMaster-Carr 94035A208
    • MSC Industrial 67313726
    • Pic Design 4423
    • RAF 6931-SS
    • WM Berg PZ-14-3
    • MS51576-14

Visit our cross reference chart and plug in your part number to see if a functional equivalent is available. Popular precision shoulder screw brands include: Amatom, Cambion, Concord, Globe, HH Smith, Keystone, Lyn-tron, Misumi, Pic Design, RAF, Unicorp and WM Berg. A comprehensive selection of Precision Shoulder Screws is also offered by McMaster-Carr (tight tolerance series), MSC, and Grainger.

We encourage you to check out our Precision Shoulder Screw Buyer’s Guide on our blog where we share “Five things you need to know” to have the most efficient shopping and buying experience.

Send us your part number
to see if we can cross to a functional equivalent,
shorten lead times & save you money!

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Five Reasons to buy from MF Supply

  1. Huge inventory including 18-8, 303, 316, 416, A2, A4 stainless in Inch & Metric, including major brands and functional equivalents
  2. Domestic parts with full paperwork and Certificate of Conformanceavailable
  3. Custom Sizes, Materials and Plating options available
  4. Creatively solve problems including hard to find parts and long lead times
  5. WBE/WOSB Woman Owned Certified Small Business

Brand Equivalent Case Study: Achieving faster delivery & lower costs using functional equivalents

October 9, 2018

Here at MF Supply we spend a lot of time sourcing hard to find, back-ordered or out of stock OEM hardware brands for our customers. Much like brand-name pharmaceuticals such as Tylenol and Advil are available generically (as acetaminophen and ibuprofen), some brand name fasteners are also available as “generics,” “crosses,” “alternatives” or “functional equivalents.”  In the world of fasteners, a functional equivalent fastener is a part that is the same as the brand-name product in form, fit and function, including material and plating specifications.  Using equivalents and alternatives to OEM brand names can be a smart way to reduce long lead times and/or cut expenses.

Check out this Case Study where an OEM brand was substituted with a functional equivalent, reducing costs by 59% and shaving lead time by over 20 weeks.  This time and money savings gave the manufacturer an advantage over their competition, which helped them win the job.

Smart Manufacturers use equivalents to shorten delivery times and win business


A Tier 3 aerospace manufacturer of subassemblies is bidding on a job for a large international Aircraft OEM where the bill of materials calls for 172 pieces of a 1/4-28 x 1/2-20 Floating Key-Locking Insert in A286 stainless steel with a Fairchild/Alcoa Keensert® part number KNKDL428JT.  As the part is in nonstock status at Alcoa, the delivery time is 28-29 weeks (yes that is half of one year which can be standard for aerospace related and mil-spec parts).  Here is the dilemma – based on this delivery schedule, the manufacturer cannot meet their prospective client’s two month delivery requirement.


MF Supply gets a print of the part and is able to cross it to an exact functional equivalent for an alternative brand we distribute.  Our factory can manufacturer and deliver the part in 4-5 weeks at 1/2 the cost of the OEM brand fastener.  The alternative parts will be manufactured with full lot traceability and manufacturer’s test reports, a certificate of conformance and a DFARS statement.  The client (Aircraft OEM) approves the substitution and awards the manufacturer the business based on their ability to make the 2 month delivery requirement.  A Purchase Order for the Floating Key-Locking Insert is issued to MF Supply.  As promised, within 5 weeks, the complete 172 inserts, with full paperwork, are delivered to the manufacturer.  The subassemblies are produced and delivered to the end client on time and underbudget.


-MF Supply functional equivalent fasteners shorten delivery time from 28-29 weeks to 5 weeks.


-KNKDL428JT price = $200 each.  Total cost $34,400.
-MF equivalent price = $82.00 each. Total cost $14,104.


-Cost savings of $20,296 or 59% (not a typo!).
– Tier 3 aerospace manufacturer wins bid and is awarded job.
-Work is completed on time.
-Job is more profitable due to cost savings realized on inserts.
-Job has been a repeater and a money maker for Tier 3 aerospace manufacturer.

In summary, if your bill of materials calls for an OEM brand fastener or component, find out if you must have the brand name product.  In cases where a generic or equivalent alternative part will work, there might be an opportunity to save money and shorten delivery time.

How can I determine if I must use the brand name or if I can cross to a generic part?

Before you shop, check the bill of materials to see if it specifically calls out a particular brand name along with the part number. If no specific manufacturer’s name is listed, then you can typically use a  generic alternative or equivalent product?.  For more complete info, check out our July 27 blog for your 4 point checklist on determining if functional equivalents will work for your business.

For more information about MF Supply contact:

Robin Lieberman, President

Happy Manufacturing Day 2018!

Manufacturing Day® is a national celebration of modern manufacturing meant to inspire the next generation of manufacturers and occurs annually on the first Friday in October.

MF Supply was proud to be a Blue level sponsor of New Jersey Manufacturing Day, organized by the NJMEP,  which brought together manufacturers, students, supporters, government representatives and industry expert speakers at the Marigold in Somerset from 7:30A-2:30p today, October 5th.

We attended 2 breakout sessions:  The first session “Driving Industry Growth through Innovative Technology, Education and Government Support” featured private and public sector experts who discussed their approach to problem solving a myriad of business issues and red tape.  I met the Executive Director of the NJ Business Action Center, Melanie Willoughby who is known as “The Fixer”.  She told us how she helped a NJ manufacturer get a special crosswalk built on a state road so their workers could walk directly from their plant to the deli across the street.  It’s the little things that count!

The second session “Women in Manufacturing Roundtable Discussion” featured three powerhouse women representing the food, machine shop and clothing/sewing manufacturing industries.  It was inspiring to hear how these three women are growing their businesses in the male dominated manufacturing space.  Perhaps the coolest story was told by panelist Tom Bergeron, the Editor of ROI-NJ.   He introduced us to the camp Tools and Tiaras, where this part summer, his daughter learned how to solder and build from industry experts in the housing and building industries. Resources for women are expanding and the the future for Women in Manufacturing looks very bright!

Other breakout sessions included:

  • Tariffs – How to Apply For Exclusions
  • Emerging Topics in Food Safety
  • Tips for Recruiting, Retaining And Linking into Underutilized Talent Pools
  • 2018 Tax Reform – How to Make The Changes Work In Your Favor

Check out the manufacturing day activities and Manufacturing Award winner announcements in your neck of the woods by visiting your state’s Manufacturing Extension Program wesbite or the Manufacturing Day website for more info.

For more information about MF Supply contact:

Robin Lieberman, President


Buyer’s Guide to One and done Keensert® Ordering

keenserts installation

Your 5 point checklist to getting it right the first time

What is a Keensert®?

Keenserts® are solid bushing style inserts that are threaded on both the inside and the outside, and have wedges or “keys” attached at the top. They are generically called key-locking inserts, and are used to distribute loads and repair or strengthen threads against failures due to stripping, seizing or corrosion. They are commonly used in precision manufacturing and aerospace applications.

Although the name Keensert® is often used generically (like Band-Aid® or Kleenex®), Keensert®  is the registered trademark of Huck Patents (its close cousin, the Keysert® is a registered trademark of Alcoa Fastening Systems.).

How do I simplify my buying process to get what I need to complete the job on time and right?

We are all familiar with that classic adage “Measure twice, cut once”.  Nowhere is this more relevant than in the world of manufacturing.  If you are involved in procurement, you are challenged with making sure you have the right parts available at the best price  so your factory can deliver on time and on budget.   Missing tools, incorrect paperwork and long delivery times can cause major headaches and negatively impact service levels.

Our goal is to help you make the Keensert buying process easier, which in turn will eliminate stress, reduce multiple shipments and potentially increase your profits.  The result?  Happier customers (and finance departments too)!  So here it goes…..

  1. Make sure to order the correct part.

Due to the price, availability and high minimum order requirements of Huck or Alcoa branded Keensert® parts,  using functional equivalents including Mil-Spec parts has become a common practice.   Request that your supplier makes reference to the part number listed on your bill of materials on their sales order and packing slip. This will ensure you are getting the functional equivalent that you need.

If you are not ordering by part number, make sure to call out both the internal and external thread including the thread class (UNC, UNF, UNJ), the material and plating, and any special finish you need.

  1. Place blanket orders for your total project needs to get the best price and ensure availability of parts when you need them.

Most standard size non-locking miniature and thin wall / light weight Keenserts® are readily available off the shelf in 303 stainless steel or carbon steel.  However, some locking style, nonstandard diameters, 4140 alloy, A286, heavy duty, extra heavy duty, solid and floating style Keenserts® are available only by special order and usually involve a long lead time.  Make sure to get current price and delivery and order parts as early as possible.  Many suppliers allow you to order now and ship later, which can prevent delivery delays.

If you have an ongoing project, calculate your total needs and place your order with staggered delivery dates.  This will get you the best available pricing and ensure you have the parts when you need them.  Remember, price breaks can start at as few as 100 pieces.

  1. Order (the correct) installation tools with Keenserts® for maximum efficiency.

Whereas most common size and material installation tools are readily available off the shelf, less popular sizes and materials might involve a lead time.  Parent materials harder than RC30 or Anondized Aluminum may require that the tapped holes be broached for the keys, which requires the use of broach blades.


broaching tool

In addition, there are manual and power installation tools to choose from, so consult with your supplier on which tool is correct for your job.  Note:  manual tools work well for jobs up to 999 Keenserts®.  For installations of 1000 Keenserts® or more, a pneumatic tool is recommended.

  1. Order the Correct drills and taps for proper installation

Although Keenserts® are installed with standard drills and taps (plus the installation tool and a hammer) each part has a specific hole/tap dimensional recommendation. The drills used are often oversized for the external thread size.  When purchasing key-locking inserts, check with your production department to make sure you have everything you need for proper installation. Note: Drill is oversize see charts for proper dimensions.

Kits are handy to have in the shop and are available for most common sizes.  These kits include 2+ Keenserts®, the associated drill, tap and manual installation tool along with instructions for correct installation.

  1. Request COC, MTRs, DFAR and all required paperwork on your RFQ and PO.

Since using functional equivalents including Mil-Spec parts is a common practice, make sure you have dotted your i’s and crossed your t’s when it comes to paperwork.  Ask your supplier to reference the branded part number listed on your bill of materials on their COC and packing slip to make sure you are getting the functional equivalent that you need.  In most cases, a Certificate of Conformance or a COC referencing the part number you ordered is all the paperwork you need.  Certain aerospace customers need a complete Manufacturer’s Test Report (MTR) package including DFAR statement and passivation certs with full lot traceability.  This might involve a fee, so include it in your RFQ.  Whatever your requirement, include it on your Purchase Order to make sure you have what you need to satisfy your customer’s needs.

In summary, follow this handy 5 point guide when ordering Keenserts® and watch your costs decrease and your service levels soar!

For more information about MF Supply contact:

Robin Lieberman, President

Buyer’s Guide to Metric Dowel Pins

dowel pin

7 Things to Know When Buying Metric Dowel Pins

This guide is a follow up to our Dowel Pin Buyer’s Guide published May 2017.  This post is specifically written to share with you the available options when it comes to procuring precision Metric dowel pins.

Our goal is to help simplify the buying process and guide you in the critical selection factors for this sometimes complex and confusing category of fasteners.

1. What standards are Metric Dowel Pins made to? 

Metric dowel pins are tricky because they fall into two buckets:

  1. DIN / ISO standard – These metric Dowel pins are readily available in the commercial marketplace and in addition to your suppliers, can be procured through national catalogers like Mcmaster-Carr, Grainger and Holo-Krome. They come on steel and stainless steel.
  2. Precision Metric Dowel Pins – These “Precision” dowel pins are manufactured by precision component brands such as Pic Design, WM Berg and Unicorp who have their own technical specifications and are not governed by DIN or ISO standards. They are usually only offered in stainless steel through distributors of precision components.

2 . What are the specific criteria I can select for Metric dowel pins?

Here is a list of the criteria and available options available:

  • Size
  • Material
  • Hardened or Unhardened
  • End style
  • Tolerances

3 . Can you list the standard and precision dowel pins available off the shelf?

4. Which types of metric dowel pins are available in which sizes and materials? 

Use this handy grid to understand the sizes and materials available in each Metric dowel pin style.

Tolerances / Fit
ISO 2338
ISO 2338A
Rounded or beveled 
Steel (least common)
300 Series Stainless Steel including
A1=18-8, 303, 304
M6 diameter tolerance
Slightly Oversized
aka Press Fit
ISO 2338B
Rounded or beveled
300 Series Stainless Steel
A1=18-8, 303, 304
H8 diameter tolerance
DIN 6325
DIN 6325H
ISO 8734A
ISO 8734
Rounded on one end
Beveled on one end
Alloy Steel
M6 diameter tolerance
Slightly Oversized
aka Press Fit
Hardened to
RHC 52-62
Precision Unhardened
300 Series Stainless Steel
M6 diameter tolerance
Slightly Oversized
aka Press Fit
Precision Hardened
Rounded on one end
Beveled on one end
416 Stainless Steel
M6 diameter tolerance
Slightly Oversized
aka Press Fit
Hardened to
RHC 36-42

Important note:  All pin options may not be available in all sizes and materials.

5. When ordering, do I need to specify the dowel pin tolerance or call out attributes such as standard, undersized or oversized fit? 

Metric dowel pins can show up under DINs and ISO numbers, including : DIN 7, DIN 6325, and ISO 2338 and 8734. When ordering DIN/ISO dowel pins it is best to include the Diameter, Length, Material, DIN or ISO and tolerance.  For non DIN/ISO Precision metric dowel pins, you can order by the manufacturer part number, such as Pic (MDP series), WM Berg (DM Series), or Holo-Krome.

6. Can I specify if I need radius (round) or chamfer (bevel) on the pin ends?

The pin style will depend upon the spec and the material. Precision dowel pins may come with either a double chamfer, double radius, or a radius on one end and a chamfer on the other end.  Check with the handy grid above for guidance.

Important note:  The configuration of the ends of unhardened metric dowel pins are at the discretion of the manufacturer.  If you have a specific style requirements, you might need to special order which usually involves a minimum and a lead time.

7. What if I need domestic or DFAR certified Metric dowel pins? 

If you are ordering by a Precision Manufacturer part number, you are in luck!  Most of the stainless steel pins produced by Pic, WM Berg and Unicorp qualify as DFAR compliant and full certifications with material certs and test reports are often available for USA made parts for a fee.

Metric Dowel Pins at MF Supply

We offer:

  • The full range of commercial Metric Dowel pins including parts that are USA made, DFARS and ROHS compliant.
  • Metric sizes including ASME ANSI B18.8.2, DIN 7, DIN 6325, and ISO 2338 and 8734
  • Metric Precision Dowel pins including Press-Fit Series and all MD series pins in 416 and 303 Stainless Steel.
  • Brand names and generic equivalents.
  • Custom-made parts per print in non-standard sizes and exotic materials and finishes.
For more detailed information about Metric Dowel Pins, to request a line card, or to send an RFQ, visit our website. And if you don’t see what you need listed, as always, ask us. “Finding the right screw for you” is our tag line after all!
Contact me at with your questions, comments or helpful hints!

About Us

For more than 40 years, MF Supply has helped American manufacturers streamline operations, saving them time and money with our sourcing expertise and unique supply chain strategies. We are a WBE/WOSB certified stocking distributor of fasteners and electronic components.

We work with the best-established factories in the United States and DFARS-certified countries, and stock a huge inventory including all major brands and equivalents. MF Supply provides solutions including: same-day drop ship direct from the factory; custom sizes, materials and plating options; and DFARS parts with full paperwork and Certificates of Conformance.

We creatively solve common problems including hard-to-find parts and long lead times. Our sourcing and reworking expertise includes fast turnaround for modification of existing parts, hard to find standards and specials, special threads, non-standard diameters and lengths, exotic materials, special platings and short runs. We provide functional equivalents to expensive brand name fasteners and help our customers save money while reducing lead times.

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Smart Manufacturers Use Blanket Purchase Orders to Reduce Risk

Learn to Hedge Against Inflation through Proactive Purchasing


The world of manufacturing is filled with risks. Staff turnover, overseas competition and third party vendor issues can all threaten your service level and put pressure on your organization. But one of the biggest risks in 2018 is inflation.


Rising material prices and inflationary forces are impacting costs at every level. Master suppliers are reporting price increases of 7%+ on steel products and 10%+ on stainless steel. What is a manufacturer to do?


One of the most powerful ways to mitigate the risk of rising prices is through a proactive supply chain strategy that includes issuing Blanket Purchase Orders (BPO). With a stable price for a fixed period of time, the BPO serves as a hedge against inflation.


  1. What is a Blanket Purchase Order?

A blanket Purchase Order is a contract to buy parts at a guaranteed price within a specific time period or schedule (typically one year). For example, a manufacturer forecasts to use 10,000-12,000 pieces of an MS16555 stainless steel dowel pins annually. They issue their supplier a Blanket PO for 12,000 pins a year at a negotiated price with 12 monthly releases of 1,000 pieces. This gives them 12 months of predictable costs at today’s 12,000 piece price, rather than tomorrow’s 1000 piece price. As we start to see double digit price increases in the industrial marketplace, the savings multiply.


  1. What are the benefits of Blanket Purchase Orders?

A Blanket PO can add certainty to a business and can make your production process leaner, guaranteeing the price and availability of parts without the burden of holding the parts in stock. Suppliers also benefit because they have a predictable revenue stream. Both sides have certainty concerning quantity, price, delivery requirements and payment terms.


Beyond certainty, the top benefits of BPOs for manufacturers are:

  • Reduces unit costs through quantity discounts.
  • Guarantees pricing & reduces time spent on price negotiation.
  • Shortens lead time and eliminates stock outs.
  • Assurance of quality of products and vendors.
  • Improves efficiency of ordering, receiving and bill paying process.
  •  Leaner operations with reduced stock burden.


During inflationary times, the benefits of locking in today’s prices for up to 1 year multiply.


  1. When should a manufacturer issue a Blanket PO?
  • When an item has a high minimum annual usage ($500 minimum EAU).
  • When a quantity discount can be achieved.
  • When you are already making repetitive purchases from the same supplier within a certain time period (typically 1 year).
  • When parts are used according to a production schedule.
  • When parts have a lead time.
  1. When should a manufacturer NOT issue a Blanket PO?
  • When minimum annual usage of item is low (under $500).
  • When part is only used for project work and usage in unpredictable.
  • When price is subject to change without notice.
  • When quality of product or supplier is questionable.


  1. What other factors should I consider?

The main risks when using Blanket Purchase Orders occur when BPOs are not monitored or extended past their final scheduled release, which can lead to price changes and inventory availability problems. The best way to mitigate this risk is through the use of an effective spend management tool that includes a minimum safety stock level. Collaboration with your supplier is also recommended.


The other main risk occurs when a blanket order is issued for more than the needed quantity of a specific part due to demand forecast issues or product changes. This risk can be mitigated by working with your supplier to set conditions to manage this gap, such as extending a 1 year blanket to 18 months.


Blanket Purchase Orders at MF Supply:

Here at MF Supply, we can help you effectively craft a proactive BPO strategy based on your organization’s unique needs. We offer blanket orders for up to 18 months with flexible terms and low minimums.


For more detailed information about Blanket Purchase Orders, to request a line card, or to send an RFQ, visit our website. And if you don’t see what you need listed, as always, ask us. “Finding the right screw for you” is our tag line after all!

Contact me at with your questions, comments or helpful hints!


Buyer’s Guide to Set Screws

where to buy set screw

8 Things to Know When Buying Set Screws

Our goal is to help simplify the buying process for this sometimes-complex category of fasteners by detailing the most critical things you must know when buying Set Screws.

  1. What is a Set Screw?

A Set Screw is a fully threaded headless screw that is traditionally classified within the socket family of products. It is generally used to fasten an object within or against another object by exerting pressure rather than holding parts together with threads. It is normally used without a nut.

  1. Who uses Set Screws?

Set Screws are used in many industrial and mechanical devices, particularly in assemblies with rotating items such as pulleys or wheels, where a component is locked onto a shaft. Designed to fasten one object inside another, Set Screws pass right through a threaded hole in the outer object and are tightened against the inner object. Pretty cool, right?

Check out this video for a demonstration of installation and application.

  1. What materials and platings are available?

The three most common Set Screw material options are alloy steel, stainless steel and brass.

The most commonly available material is hardened alloy steel with a thermal black oxide finish, as per ASME B18.3 and a Rockwell hardness of C45-53.

Stainless steel grades 18-8/303 and Metric A2 are also commonly available. Other exotic materials such as brass, 316 or A4 stainless steel, 4140 steel, 416, A286 or special finishes including zinc plating may be available for special order with a lead time.

Socket Set Screws come standard with 3A thread fit. Some sizes and materials may be available with nylon patches or pellets.

  1. What sizes are available?

In our experience, Set Screws are most commonly available in sizes 2-56 through 1″ in imperial and M2-M24 in metric diameters with a hex socket drive on one end and a cup point on the other.

  1. What information should I provide to get an accurate quote?

The easiest way to order is by part number. The most popular manufacturers of Set Screws are Holo-Krome, Blue Devil and Misumi, along with the national catalog houses like McMaster-Carr, Grainger and MSC Industrial.

If you don’t have a part number, you’ll need to provide the diameter and thread, the body length, drive and tip type, material and plating.

  1. Other than size, material and plating, what other options are available?

The other main considerations when selecting Set Screws are the drive and the point.  We offer a comprehensive look at your options below.


The most common and readily available drive style is a hexagonal socket drive (think Allen wrench), however, Set Screws may also be available in slotted, six-lobe (Torx) and spline drives for certain sizes.


This is where it gets interesting. The point of the Set Screw determines its function. Seven (yes, seven!) main points are available, each serving a slightly different purpose.

Cup The most common style, which is slightly cupped to meet the surface of the inner object. Used for permanent or semi-permanent installations, the Cup point provides a high level of security and control. (Metric DIN 916)

Knurled Cup  A variation of the Cup point, this style has knurls for a stronger grip.

Cone A very sharp point wedges into the inner object to hold it permanently in place. With the highest holding power of all Set Screw styles, the Cone point is used for permanent settings. Note: Cone point Set Screws may cause damage to the inner object which might not be desirable in some applications. (DIN 914)

Flat – Designed for flexibility when frequently resetting or relocating objects on hard steel shafts where minimal damage to the shaft is desired. Affordable and easy to install, Flat point Set Screws can be moved without damaging the inner object. (DIN 913)

Oval The Oval point is the inverse of the Cup point. The small rounded contact surface allows slight adjustments without loosening the screw and causes minimal surface damage to the inner object. The Oval point Set Screw is the most practical type for situations where the inner and outer objects require regular adjustments.

Half-Dog Sometimes offered as a Full-Dog point, its protruding tip locks within a mating hole or slot in the shaft, for permanent setting. Half-dog/Dog points are sometimes used instead of a dowel pin. (DIN 915)

Nylon tip – Resembling a Half-Dog point, the soft nylon tip is used to grip curved or textured surfaces.

  1. What other factors should I consider?

We’ve covered the most common variables including head style, diameter and thread, length, material and plating or finish. Here are a few of the other considerations you might be faced with based on the project and the bill of materials:

Do you need domestic parts (i.e. Holo-Krome) or will imported screws work?

Do you require parts that conform to a specific mil-spec number, such as AN565, NAS1081, MS18063, MS18064, MS18065, MS18066, MS18067, MS18068, MS21342, MS51017, MS51021, MS51022, MS51023, MS51025, MS51026, MS51029, MS51031, MS51033,MS51038, MS51040, MS51045, MS51047, MS51053, MS51476, MS51477, MS51963, MS51964, MS51965, MS51966, MS51973,MS51974, MS51976, MS51977, MS51981, MS51982 with their exacting tolerances and traceability, or will standard commercial parts work?

Does your bill of materials call out a specific manufacturer, such as Holo-Krome or Blue Devil?

Make sure you have the correct installation hardware (Allen wrench or hex key) to go along with your Set Screws.

  1. What level of certification is required?

Generally, a Certificate of Conformance or a COC is sufficient for your customer. Full certification with material certs, DFARS certification and test reports are often available for USA-made and mil-spec parts for a fee.

Here at MF Supply, we offer:

  • The full range of commercial and mil-spec parts, including parts that are DFARS and ROHS compliant.
  • Brand names (Holo-Krome) and generic equivalents.
  • Custom-made parts per print in non-standard and exotic materials and finishes.
  • Inch and metric sizes, including DIN913, DIN914 and DIN915.

For more detailed information about Set Screws, to request a line card, or to send an RFQ, visit our website. And if you don’t see what you need listed, as always, ask us. “Finding the right screw for you” is our tag line after all!

Contact me at with your questions, comments or helpful hints!



Four things you need to know when buying Captive Panel Screws

Captive Panel Screws New Jersey

Captive Panel screws are a type of screw that remains attached to the parent material when separated from the mating part. These special screws are used to fasten PC boards, cabinets, drawers, furniture, equipment panels and more. But, what exactly are they and what should you know before getting a quote or buying them? We’d like to help you out with this four-point buyer’s guide.

  1. What are Captive Panel Screws?

Captive Panel Screws provide simple and secure mounting of hardware to panels and other assemblies. These special fasteners reduce the risk of lost parts and damage from loose screws falling into moving parts. They allow for speedy repeated assembly and disassembly operations. Used along with retainers, washers, nuts or springs, these screws come in a variety of sizes, styles and materials.

  1. What information should I provide to get an accurate quote?

The easiest way to order is by manufacturer part number. The most popular manufacturers of Captive Panel Screws are: Amatom, Concord, Globe, Grainger, H.H. Smith, Lyn-tron, Misumi, McMaster Carr, MSC Industrial, RAF and Unicorp. If you don’t have a part number, you’ll need to specify the style and there are many! Styles are generally represented by a number (1 through 6) or a letter (A, B, C, D, E). Other than style, you’ll need the head style, drive type, shank length, thread, point type, material and plating. For example, a popular Captive Panel Screw is a 1/4 -20 x 1” Long Hex Socket Drive Captive Panel Screw in 18-8 stainless steel.

  1. What sizes and materials are available off the shelf?

Depending on the manufacturer and style, Captive Panel Screws are available off the shelf in inch sizes starting as small as 4-40 thread up to 3/8-16 in both coarse and fine thread. Metric Captive Panel screws are available from M3 through M6 and are most common in coarse thread.

Common materials are brass, steel and 18-8 stainless steel.

Threads, head sizes, shank sizes, screw lengths and screw tips are related to the style of the Captive Panel Screws and all sizes may not be available in all materials and styles.

As always, special lengths, sizes and materials are available but may involve a lead time – just ask!

  1. Are there other factors to consider?

YES! One surefire way to save money and shorten delivery time is to cross the OEM brand part on your bill of materials to a functional equivalent.

Finally, although Captive Panel Screws can be installed easily with thumb pressure, and many times don’t require specialized equipment for installation, methods to attach the screw to the parent material include using split washers, springs, nuts and retainers.  Make sure you order the proper mating parts to complete your Captive Panel Screw assembly.

For more detailed information about Captive Panel Fasteners, to request a line card or to send an RFQ, visit our website. And if you don’t see what you need listed, as always, ask us. “Finding the right screw for you” is our tag line after all!

Contact me at with your questions, comments or helpful hints!


Buyer’s Guide to Mil-Spec Fasteners


7 things you need to know

If you sell to the military either directly or indirectly, then you are probably familiar with Mil-spec fasteners. But, what exactly are they and what should you know before buying them? We’d like to help you out with this Seven point buyer’s guide.

  1. What does Mil-spec mean anyway?

Mil-spec or MIL-STD, is the informal name for the military standard the U.S. Department of Defense uses in the production of military equipment. Critical fasteners and components used in the production, repair and maintenance of this equipment are classified as “Mil-spec” fasteners. These parts are usually designated by an AN, MS, NAS or NASM prefix followed by a part number (i.e. MS24693C-4). Each of these prefixes is an abbreviation: for example: NAS stands for National Aerospace Standard and MS stands for Military Standard.

  1. What’s the difference between Mil-spec and commercial fasteners?

Mil-spec fasteners look a lot like their civilian cousins, but these little guys are made to a specific standard that defines in detail, the screw’s attributes, including: dimensions, tensile strength, hardness, threads, drive type, material qualities and plating, just to name a few. Mil-spec fasteners are even traceable by lot to designated manufacturers. The government maintains a list of factories that are qualified to manufacture and distribute Mil-spec fasteners. These suppliers have met all the government’s requirements and pass the highest quality control standards. This designation is called Qualified Suppliers List for Manufacturer’s [QSLM]. Commercial fasteners are not held to such specific and exacting standards.

  1. Who uses Mil-Spec Fasteners?

Mil-spec fasteners are used by anyone manufacturing or servicing military equipment. How do you know if your project requires Mil-spec parts? Often, the bill of materials (BOM) calls for specific Mil-spec grade fasteners in accordance with a part number, drawing, NIIN or NSN or procurement requirement. Some of the most common uses of Mil-spec fasteners include aerospace and naval vessels.

  1. Do Mil-Spec fasteners have different features and standards than commercial fasteners?

Mil-spec parts are manufactured and tested to strict military standards ensure performance and reliability. In general, commercial fasteners will not have the same exacting quality standards. Let’s look at a specific example and compare the Mil-Spec MS24693-C4, which is a 4-40 x 3/8 Phillips Flat 100 degree Machine screws in 300 series stainless steel, to its commercial cousin.

Features of the MS24693C-4:

  • ­  Manufactured in an QLSM approved factory
  • ­  Made/melted in the USA or other DFARs* approved country
  • ­  Materials to procurement spec FF-S-92, SAE AIR 4127
  • ­  Cleaned, descaled, passivated to AMS-QQ-P-35; AMS 2700
  • ­  Dimensions, tensile, hardness, threads, recess, head marking to AN, MS, NAS, NASM standard
  • ­   Magnetic permeability to test specs ASTM A342
  • ­  Quality Assurance to procurement spec FF-S-92 MIL-STD 1312
  • ­  Inspection system requirements per Mil-I-45208
  • ­  Full lot traceability, manufacturer’s certification and chemical and physical certification
  • ­  Available in diameters from #0 through 1/4 inch in coarse and fine thread and various lengths


Features of a 4-40 x 3/8 Commercial Phillips Flat 100 degree Machine screws in 18-8 series stainless steel:

  • ­ Manufactured per ASME B18.6.3-2002
  • ­ Thread dimensions to ASME B1.1


As you can see, the Mil-spec version is held to a higher and more exacting level of quality and testing than the commercial version. As such, the Mil-spec parts are cleaned and passivated, and tested for magnetic permeability, whereas the commercial parts are not.


5.   What level of certification is required?

Generally, a Certificate of Conformance (COC) or a record affirming a fastener has met the requirements of the relevant specification, contract or regulation is sufficient for Mil-Spec fasteners. Full certifications, which include the part name, part description, date of manufacture, lot number, chemical composition of material, and treatment of material including plating or passivation, and material test reports, are often available for a fee. It is critical to ask for the level of certification (COC, full material certs, passivation certs, etc) in advance in order to have the most efficient buying experience.

6. Are there other factors to consider when procuring Mil-spec fasteners?

Great question! Almost a decade ago, the term “DFARS Compliant Material” came to the forefront for companies supplying parts and services to the government. The original Federal Acquisition Regulation (FAR) clause 252.225-7014 specified “A Preference for Domestic Specialty Metals.” What that means in our world is that for fasteners to be DFARS compliant, the metal used to fabricate them must be melted or manufactured in the United States or a qualifying country.

Qualifying countries include: Australia, Austria, Belgium, Canada, Czech Republic, Denmark, Egypt, Finland, France, Germany, Greece, Israel, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, Turkey, United Kingdom of Great Britain and Northern Ireland.

Important Note: DFARS only pertains to fasteners made from “specialty metals” including: stainless steel, high alloy steel like Grade-BD, or Grade 5 Chromium steel with high chromium content.

To keep up to date with DFARs requirements, visit

  1. Where can I find a list of Mil-spec fasteners and specs?

The Defense Logistics agency is a great resource. They maintain a comprehensive database of specifications and drawings. They also maintain a catalog of hardware that includes NIINs and NSNs that sometimes called out in a bill of materials. Check out the following links for more comprehensive information regarding hardware:  – to view catalogs of mil-spec parts and specs by category   – To look up a specific part – To see MF Supply’s Mil-Spec fastener stock – To download MF Supply’s Mil-spec line card


For more detailed information about Mil-Spec parts, to request a Mil-Spec Line Card or to send an RFQ, visit our website. And if you don’t see what you need listed, as always, ask us. “Finding the right screw for you” is our tag line after all!

Contact me at with your questions, comments or helpful hints!

Standoffs and Spacers Buyer’s Guide

standoffs and spacers mf supply

7 things you need to know

According to the dictionary, a standoff is defined as “a stalemate or a deadlock between two equally matched opponents and a spacer is a piece of material used to maintain space between 2 things.   In the world of precision manufacturing, standoffs and spacers are mechanical components that are used the create space or join parts together, typically in PC boards.  Below are 7 things to know to have the most efficient buying process.

  1. What are spacers and standoffs?

Often classified as Electronic or Panel Hardware, Standoffs and Spacers are commonly used to mechanically support and electrically connect and position components within assemblies, typically in PC boards and instrument panels.

  1. What’s the difference between a standoff and a spacer?

Both standoffs and spacers have a hex or round shaped body, and 2 openings.  The main difference is that spacers are unthreaded with an inside clearance hole, and standoffs are threaded on both ends.  Threads may be male (external) r female (internal).

  1. Who uses standoffs and spacers?

Look inside an assembled circuit board, and you will be greeted by a bevy of Standoffs and Spacers, because in the world of Electronic Hardware, they are the standard for connecting and mounting circuit boards, panels, doors, and gears. Both are commonly used to properly position parts within an assembly, to reduce component contact, to elevate stacked sections, to ensure enough room for heat to dissipate, and to separate or create space between two objects. These guys are workhorses!

  1. What materials and platings are available?

Common materials include aluminum, brass, plastic/nylon and stainless steel. Common platings include clear anodized, nickel, gold iridite and zinc plated. There are over 20 common platings available! Here is a guide to most common materials:

  • Aluminumis popular because of its ratio of weight to strength. It is light, non-magnetic, performs well in severe temperatures, and has insulating properties.
  • Brassis used in making high-quality standoffs. It is conductive, resists corrosion, and is non-magnetic. It is costlier and heavier than aluminum and is usually plated zinc or nickel.
  • 18-8 Stainless Steelis strong, conductive, nonmagnetic and offers excellent corrosion resistance.
  • Nylon 6/6is superlight, nonconductive, and resistant to chemicals and solvents.

316 stainless steel, alloy and other exotic materials, and special diameters and lengths are available in certain sizes and/or for special order and usually involve a lead time.

  1. What sizes are available off the shelf?

Standard stock sizes run from 3/16 – 1/2 body diameter, 1/4 to 2” long with threads starting at 2-56 running through 1/4-20 and clearance holes ranging from #2 though 1/4”. Metric stock sizes run from M3.5-M6 body diameter with M2.5, M3 and M4 threads.  Remember, the lengths and threads available depend upon the diameter of the body and not all size configurations will be available.

As always, special lengths and sizes are available – just ask!

  1. What information should I provide to get an accurate quote?

The easiest way to order is by manufacturer part number.  If you don’t have one, you’ll need to specify body diameter, body shape (hex or round), body length, thread size & gender (male or female), material and plating.  For example, a popular standoff size is a 1/4 hex x 1/2 Long x 10-32 male Standoff in Stainless Steel.

  1. Are there other factors to consider?

YES! One surefire way to save money and shorten delivery time is to cross the OEM brand part on your bill of materials to a functional equivalent.  Popular brands include: Amatom, Concord, Globe, H.H. Smith, Lyn-tron, Microplastics, Keystone, Pem, RAF, Unicorp.

Finally, standoffs and spacers sometimes show up under their Mil-spec numbers, which can be crossed to commercial equivalents. Some common Mil-spec series include NAS42, NAS43, NAS61, NAS1056, NAS1057, NAS1829, NAS1831. Where applicable, these Mil-spec parts will be DFAR compliant with full paperwork.

Contact me at with your questions, comments or helpful hints!