BOLT, MACHINE (P/N an4-20) - New Surplus

The AN4-20 is a 1/4-inch hex head machine bolt with 28 UNF-3A threads manufactured to AN (Army-Navy) specifications, now maintained under NASM standards. Fabricated from alloy steel for strength and durability in aircraft structural and system assemblies. Used primarily in control linkage clevis joints and fastening applications throughout airframe MRO and production work.

Installation requires selecting proper grip length for the specific stack-up and using approved hardware per aircraft maintenance manual specifications. Verify part eligibility in the Illustrated Parts Catalog before installation.

What is the BOLT, MACHINE (P/N an4-20)?

The AN4-20 is a 1/4-inch hex head machine bolt with 28 UNF-3A threads manufactured to AN (Army-Navy) specifications, now maintained under NASM standards. Fabricated from alloy steel for strength and durability in aircraft structural and system assemblies.

Does the an4-20 meet AN/MS/NAS aviation specifications?

Aircraft hardware is manufactured to military and aviation specifications. The BOLT, MACHINE conforms to its applicable AN (Air Force-Navy), MS (Military Standard), or NAS (National Aerospace Standard) specification. Contact us for specific specification details.

What material is the an4-20 manufactured from?

Aviation hardware is available in various materials including cadmium-plated steel, stainless steel, aluminum alloy, and titanium depending on the application. Contact us for material certification and specifications for the an4-20.

Can I order the an4-20 in custom quantities?

Yes, we sell hardware in various quantities from single units to bulk lots. The BOLT, MACHINE is available in: New Surplus. Submit an RFQ for volume pricing or call (904) 998-9101 for quantity availability.