MS16555 Dowel Pins in Stock!

At MF Supply, we have a large selection of Precision Dowel Pins and Mil-Spec Hardware. The product we want to highlight today is the MS16555 Dowel Pin.

What is the Mil-Spec Dowel Pin MS16555?

The MS16555 is a stainless steel, cylindrical, solid, and headless fastener. The MS16555 is classified as a Mil-spec fastener, made to a specific exacting 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 is the informal name for the military standard the U.S. Department of Defense uses in the production of military equipment. Mil-spec fasteners are usually designated by an AN, MS, NAS or NASM prefix followed by a part number.  Each of these prefixes is an abbreviation: NAS stands for National Aerospace Standard and MS stands for Military Standard.

Dowel Pin Uses

Dowel pins are broadly used in various applications, including aerospace, electrical motors, hydraulic equipment, instrumentation, and more.

They’re used as a hinge, shaft, or pivot, and are used to locate or hold parts together within a precision assembly or a fixture, often when things are moving within that assembly.

MS16555 Dowel Pin Options

The MS16555 series is classified as a press fit style dowel pin with a diameter tolerance -0/+ .0002 over nominal size. These Mil-spec dowel pins are DFAR & RoHS compliant & may be requested with manufacturers COC & Full material certifications.


  • 416 or 400 series hardened stainless steel
  • Plain alloy steel
  • Phosphate finished alloy steel

MS16555-1 through MS16555-145 are Alloy Steel plain finish

MS16555-301 through MS16555-444 are Alloy Steel phosphate finish

MS16555-601 through MS16555-744 are 410 or 416 CRES Stainless Steel hardened with passivation.


Diameters range from 1/16 (.0626-.0628) through 1 inch (1.0003-1.0001). Lengths range from 3/16 to 6 inched long. For price and availability, send us an RFQ directly from our product pages.

Why Choose MF Supply for MS16555 Dowel Pins?

  • The MS16555 Dowel Pin is our most popular military spec dowel pin
  • They are made in the USA and are DFAR compliant.
  • Certification paperwork is available.
  • We have extensive stock, in NJ and at our distribution centers, which means no delay in delivery.

Learn More About MF Supply and our Products

We are excited for you to know that some products lines including CRES series MS16555 are available for purchase on-line. Additional dowel pin & mil-spec resources include:

Dowel Pin Data Sheet 2019

Buyer’s Guide to Mil-spec fasteners

Dowel Pins Buyers’ Guide

Metric Buyer’s Guide 

We stock a huge selection of Mil-spec fasteners in both Alloy & Stainless Steel with full DFAR & RoHS paperwork. Factory drop ship available for thousands of parts!

If you are interested in learning more about these dowel pins or any of our other fasteners or PPE, contact us today!

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.

MF Supply Work With Us

Six Reasons To Buy From MF Supply

  • Full eCommerce Enabled Website With Technical Manual Available 24/7 – Visit our website and Create a New Account, track online orders, browse our product catalog, check technical specs, subscribe to our blog, or buy online.  We are adding items and improving functionality daily!
  • Same Day Shipping From The USA – Our hardware products are in stock and ship to you directly from our USA based distribution centers. 
  • Functional Equivalents To Expensive Brand Names- We stock and source alternatives to brand name fasteners, reducing long lead times and saving you money.
  • Creatively Solve Problems – We are sourcing experts, offer competitive pricing and specialize in finding hard to find parts and reducing long deliveries.
  • One-Stop Shopping On Certified Hardware – We stock and source a full line of fasteners including Mil-Spec, DFARS compliant and other industrial products.
  • WBE/WOSB Woman Owned Certified Small Business – To meet your diversity & set-aside needs.

MF Supply is a WBE/WOSB certified supply chain partner to business, industry and government.  We are sourcing experts and stocking distributors of Hardware, Precision & Mil-Spec Fasteners and Safety supplies.  For more than 50 years, we have been supplying manufacturers in the electronics, industrial, commercial, aerospace and military markets with the full range of fastener products and services.  Our Cage Code is 58QG4 and our registered name is RL Supply Inc dba MF Supply. 

What the heck are Dowel Pins?

Dowel Pins

Welcome back to our “what the heck is that” series, where we discuss some of the unique fasteners and electronic hardware that manufacturers use in the design and assembly of their products. Today, we will introduce you to the Dowel Pin.

What is a Dowel Pin? 

If you have ever shopped at Ikea or assembled furniture on your own, then you are familiar with the peg shaped non-threaded wooden pins that are used to join parts together, aka as a Dowel Pin.

For the purposes of manufacturing, Dowel Pins are solid, headless cylindrical shaped straight metal pins with a centerless ground finish. Typically hardened and manufactured to precise fractional diameters and lengths, Dowel Pins come in a variety of sizes, styles, designs and materials that cause confusion among buyers, engineers and end-users alike! Today, we will try simplify this confusing category of fasteners.

Who uses Dowel Pins?

Dowel Pins are used as a hinge, shaft or pivot to locate or hold parts together within a precision assembly or a fixture.

They are broadly used across various applications in many industries, including: aerospace, electrical motors, hydraulic equipment, instrumentation, tooling and fixtures, machinery, military and many more.

Dowel Pins are popular within assemblies since they can withstand frequent insertion and removal without distortion.  And production favors pins since they require no extra fastening hardware for insertion, no secondary operations and no mating parts.  All this adds up to speedier production, which makes everyone in the food chain happy!

What do I need to consider when selecting Dowel Pins?

Although Dowel Pins are offered in a multitude of materials and styles, when it comes to the main commercial and Mil-spec offerings, there are a few main issues to consider.

Standard, Oversized or Undersized?

Standard series Dowel Pins are used for initial applications.  They have a basic diameter 0.0002 inch over the nominal diameter. For example, a ¼ standard dowel will have a diameter between .2501-.2503.

Oversized series Dowel Pins are usually used to fit into worn holes and are generally used in the aftermarket for repairs.  They have a basic diameter 0.001 inch over the nominal diameter. For example, a ¼ oversized dowel will have a diameter between .2509-.2511.

Undersized series Dowel Pins are used for inconsistent holes.  They have a basic diameter -0.0002 inch under the nominal diameter.  For example, a ¼ undersized dowel will have a diameter between .2500-.2498. The Mil-P-21143/2- falls into the undersized category.

Chamfer or radius on the end?

In general, commercial pins are made to inch standard ANSI ASME B18.8.2.  Standard alloy pins will have a radius on one end and a chamfer on the other end.  However, stainless steel Dowel Pins are often manufactured with a chamfer on both ends.

Commercial or Military?

If you or your customer needs domestically made, DFARs pins to the most exacting standards, then military may be the right pin for you!

Alloy or stainless? And which stainless for that matter?

Alloy Steel is the strongest pin available and is hardened. It can be finished with Black Oxide to provide greater rust resistance than plain alloy.

Type 416 Stainless steel is the strongest standard stainless steel offering, and is the material used for MS16555 and MS16556 series.  Magnetic.

Type 18-8/303 Stainless Steel is the most commonly available stainless offered and is the standard material offered for Mil-P-21143 series.

Type 316 Stainless Steel is the most corrosion resistant stainless available and does not correlate to a Mil-spec part.

Are there other factors to consider?

Dowel Pins often show up under their Mil-spec numbers, which can be crossed to commercial equivalents. Some common Mil-spec series for Dowel Pins include Mil-P-21143 (303 Stainless), MS16555 (standard series offered in both alloy and 416 Stainless Steel) and MS16556 (oversized series offered in both alloy and 416 stainless steel).

If you are not ordering by an MS or NAS Mil-Spec part number, then inch Dowel Pins conform to ANSI/ASME B18.8.2.  For commercial pins, be mindful to specify the material and size tolerance that you need. Unless noted, Dowel Pins are precision ground, hardened and heat treated to meet the proper Rockwell hardness.

And remember, no hammers! When installing Dowel Pins, never drive the pin into the hole with force, always press it in for best results.

Dowel Pins at MF Supply

We offer:

The full range of commercial and mil-spec parts, including parts that are DFARS and ROHS compliant.

Brand names and generic equivalents.

Custom made parts per print in non-standard and exotic materials and finishes.

Inch and Metric sizes including DIN 7, DIN 6325, and ISO 2338 and 8734


For more detailed information on Dowel Pins, visit us at