Are you searching for certified Mil-Spec fasteners to meet your bill of requirements (BOM) or project specifications? Look no further! MF Supply specializes in sourcing and supplying domestically manufactured AN, MS, and NAS Mil-Spec fasteners for aerospace, defense, and industrial applications. MF Supply stocks over 3,000 unique certified parts from the Qualified Suppliers List for Manufacturers & Distributors (QSLM & QSLD). Mil-Spec products stocked include Keensert® Style Key-Locking Inserts, Helical (HeliCoil®) Inserts, Precision Dowel Pins, Slotted Spring Pins, Extended Prong Cotter Pins, Nuts, Washers, Machine Screws, Precision Shoulder Screws, Hex Head Cap Screws/Bolts, Socket Head Cap Screws, Set Screws, Self-Tapping Screws and more. All Mil-Spec parts undergo rigorous testing and are DFARS or domestically manufactured with Certificate of Conformance (COC) and Material and Physical certification paperwork available to ensure compliance.
Buy Mil-Spec Fasteners and Precision Electronic Hardware at MF Supply!
We Have All the Mil-Spec Fasteners and Precision Hardware You Need
We offer a huge selection of DFARS certified and domestic Mil-Spec fasteners directly on our website, making it easier for you to find exactly what you need for your project at the click of a button or via RFQ depending on your preferred method of procurement. Below is a list of some of our most popular Mil-Spec product categories available:
1 – Mil-Spec Keensert® Style Key-Locking Inserts
- Standards: MS51830, MS51831, MS51832, NA0146, NA0147, NA0148, NA0149, NA0150, NA0151, and NAS1395.
- Styles: Miniature, Thin Wall, Heavy Duty, Thick Wall, and Extra Heavy Duty
- Available Sizes: 2-56 to 1/2-13 Internal thread for inch sizes and M2 x 0.4 to M24 x 2 for metric sizes
- Materials: 4140 alloy steel, Nitronic 60, CRES A286 and 303 series stainless steel
- Applications: Can be used to create new threads, for thread reinforcement, and to repair stripped threads
2 – Helical Inserts (aka HeliCoil®)
- Standards: MS121, MS122, MS124, MS21209, MA3279, and MA3329
- Styles: Free-running and self-locking
- Available Sizes: #2-56 to 1½-6 for inch sizes and M2 to M36 for metric sizes
- Materials: CRES 300/18-8 stainless steel
- Applications: Can also be used to create new threads, for thread reinforcement, to convert threads between inch and metric sizes, and to repair stripped threads
3 – Mil-Spec Precision Dowel Pins
- Standards: MS16555, MS16556, and MIL-P-21143
- Styles: Interference/Press Fit, Undersize/Slip Fit and Oversize +.001
- Sizes: Diameters from 1/32 to 1 inch and lengths from 3/32 to 6 inches
- Materials: CRES 303, 400, 416 series stainless steel
- Applications: Can be used as a hinge, shaft, precise location device or pivot to align or secure parts within a precision assembly or fixture
4 – Mil-Spec Slotted Spring Pins
- Standards: MS16562
- Styles: Slotted
- Sizes: Diameters from 1/16 to ½ inch and lengths from 3/16 up to 3 inches long
- Materials: Alloy steel with a zinc phosphate finish
- Applications: Can be used as a hinge or shaft for the purpose of securing and fastening components together
5 – Mil-Spec Extended Prong Cotter Pins
- Standards: MS9245
- Styles: Extended Prong
- Sizes: Diameters from 1/32 to 5/32 inch and lengths from 1/4 to 1/2 inches long
- Materials: T321 stainless steel
- Applications: Designed to retain/secure a variety of fasteners such as bolts, nuts and pins in place and prevent them from sliding or coming out
6 – Mil-Spec Hex Finished Nuts
- Standards: MS51967B & MS51967C
- Styles: Grades B & C
- Sizes: Stock sizes from 1/4-20 through 3/4-10 inches thread
- Materials: Alloy steel with a cadmium yellow finish
- Applications: Used to fasten parts together by pairing and tightly securing bolts in place
- Standards: MS35649 & MS35650
- Available Sizes: Stock sizes from 2-56 through 3/8 thread
- Materials: Alloy steel cadmium yellow and 300/18-8 series stainless steel
- Applications: Typically paired with bolts or screws to ensure parts/components stay firmly fastened in place
8 – Mil-Spec Washers
- Standards: MS51848, NAS620, MS35333, MS35335, MS35338, AN960, AN960-C, AN970, MS15795, MS27183, NAS1149 & NAS620
- Styles: flat, light flat, flat machine screw, split lock, high collar split lock, internal tooth lock, and external tooth lock
- Materials: Carbon steel, Alloy steel and 300/18-8, 316, 400 series stainless steel
- Applications: Distribute the load of a fastener, such as a bolt or screw, over a larger surface area. This in turn helps reduce the effects of wear, damage or vibration on the fastener assembly by providing a cushion between the fastener head and the parent material
- Standards: MS24693, MS35190, MS35191, MS35206, MS35207, MS35265, MS35266, MS35275, MS35276, MS51957, MS51958, MS51959, & MS51960
- Styles: 82d & 100d Flat Phillips, Drilled Slotted Fillister, Philips Pan Head
- Available Sizes: Diameters range from 0-80 to 3/8-16 inches with lengths ranging from 3/32 to 3 inches long
- Materials: Carbon steel, Alloy steel, and 300/18-8 series stainless steel
- Applications: Often used in conjunction with other fastening elements, such as washers and nuts, they have uniform threads that when fastened engage with corresponding threads in a tapped hole or nut, creating a secure mechanical connection between components
10 – Mil-Spec Precision Shoulder Screws
- Standards: MS51576 & MS51575
- Styles: Hex and slotted drives
- Available Sizes: Stock sizes range from 4-40 to 3/8-16 thread
- Materials: 300/18-8 series stainless steel
- Applications: Feature a cylindrical unthreaded shoulder that serves as a dowel or pivot point for rotating parts, also used to hold parts together within a precision assembly
11 – Mil-Spec Hex Head Cap Screws/Bolts
- Style: Hex head
- Standards: MS35307, MS35308, MS90725, MS90726, MS90728G & MS90727F, B1821
- Sizes: Stock sizes range from 1/4-20 through 1-1/4 diameter
- Materials: Alloy steel, 300/18-8 Series Stainless Steel
- Applications: Their hexagonal heads allow for the application of high torque using a wrench or socket, which enables a very tight and secure fastening for load-bearing structures in military vehicles, aircrafts and more
- Style: Socket head
- Standards: NAS1352C / MS16995, NAS1351C / MS16996, MS16997, MS16998, NAS1351N & NAS1352N, & MS24671
- Sizes: Stock sizes range from 0-80 through 1-1/2 diameter
- Materials: Alloy steel, 300/18-8 series stainless steel, A286
- Applications: These screws have a cylindrical head with a hexagonal recess (socket) that allows for tightening with an Allen wrench/hex key. The socket head design allows for use in applications where there is limited space. The hexagonal socket allows for precise control during assembly, ensuring the screw is driven straight and accurately into the desired position
Can’t find what you’re looking for in the list above? Send us an RFQ with the product description or part number that you are looking for and our MF Supply team of sourcing experts will help find what you need!
Why Buy Mil-Spec Fasteners from MF Supply?
When precision, compliance, and reliability are non-negotiable, MF Supply stands out as a trusted partner for mil-spec fasteners. Here’s why industrial buyers across aerospace, robotics, defense, and manufacturing sectors turn to MF Supply:
Compliance and Certification: MF Supply’s mil-spec fasteners meet stringent U.S. Department of Defense (DoD) specifications, including MS51830, MS51831, and more. Each fastener is available with Material and Physical Test Reports, Certificates of Conformance, and DFARS/Domestic Statements—providing peace of mind for critical applications.
Sourcing Expertise: MF Supply works with the best factories across fastener categories, offering tailored solutions based on your budget, delivery and certification needs.
Reliability Across Critical Industries: Serving aerospace, defense, robotics, automotive, and manufacturing sectors for over 50 years, MF Supply is a trusted partner for industries where delivery times, precision and reliability are non-negotiable.
Shop Over 3,000 Unique Mil-Spec Fasteners and Precision Hardware Directly on Our Website!
Manufacturers working with us can expect timely deliveries, competitive pricing, and access to expert guidance to help optimize their fastener choices. Manufacturers eager to explore our Mil-Spec products’ catalog, including our other recently expanded product categories, are encouraged to visit our website at www.mfsupply.com, reach out to us at sales@mfsupply.com or request a quote. Our MF Supply team of sourcing experts will help you find what you need. “Finding the right screw for you” is our tag line after all!
Book a one-on-one consultation with our President, Robin, to discuss how MF Supply can help you solve your Industrial Sourcing, Fastener, and Safety concerns.
Your Purchasing Department’s Secret Weapon!
Here are 5 reasons to buy from MF Supply
- We Source and Deliver What Others Can’t, Faster Than You Imagined – With speedy solutions for elusive parts and lengthy delivery times – We’ve got you covered with both custom-made specials (send us your prints!) and hard-to-source options, quickly and at a fair price.
- Cost-Effective Functional Equivalents to OEM Brand Fasteners-Why Pay More? – Reduce lead times and costs with the same quality and same performance. Try us for alternatives to brands like McMaster-Carr, MSC, Misumi, PEM, and RAF and experience unmatched savings! Same form, fit and function for less.
- Huge Selection of Certified and Commercial Hardware with Same-day Shipping Available for Countless Items – We source and stock standards, specials, commercial, Mil-Spec & OEM brands in inch and metric sizes. Standards include AN, NAS, MS, IFI, ASTM, ASME, DIN, ISO, JIS. We are sourcing experts for inserts, certified Mil-Spec parts and anything in stainless steel. Many parts are available with manufacturers’ certifications, including DFAR, ROHS and CoC. Trust us to ship on-time from our national distribution centers.
- A User-Friendly, 24/7 Online Shopping Experience – Enjoy a 24/7 online shopping experience with easy-to-use filters, detailed product information, and a constantly updated technical directory. Sign up now for a seamless experience!
- WBE/WOSB Certified Woman-Owned Small Business – As a certified Woman-Owned Small Business, we support your diversity goals. Trust us to meet your fastener and sourcing needs with expertise and efficiency [Cage Code 58QG4].
