BOLT,MACH 1/4-28-5.78 STL (P/N an4-56a) - As Removed, New Surplus

The AN4-56A is a 1/4-28 UNF hex-head aircraft bolt in steel with an undrilled shank. This fastener conforms to AN/NASM4 dimensional standards for airframe applications. The undrilled shank (suffix A) pairs with self-locking nuts to prevent vibration loosening in flight-critical connections.

Commonly used in control linkages and structural assemblies where precise 1/4-28 threading is required. Installation requires matching grip length to component thickness and applying torque per aircraft maintenance manual specifications. Verify part eligibility in the Illustrated Parts Catalog before use.

What is the BOLT,MACH 1/4-28-5.78 STL (P/N an4-56a)?

The AN4-56A is a 1/4-28 UNF hex-head aircraft bolt in steel with an undrilled shank. This fastener conforms to AN/NASM4 dimensional standards for airframe applications.

What conditions is the an4-56a available in?

The an4-56a is currently available in the following conditions: As Removed, New Surplus. Each condition reflects the part's maintenance history and certification status per FAA standards.

How do I get pricing for the an4-56a?

The an4-56a requires a custom quote. Submit a Request for Quote (RFQ) through our website or call our sales team at (904) 998-9101 for immediate pricing assistance.

Do you offer expedited shipping for the an4-56a?

Yes, we offer same-day processing on in-stock items and provide 24/7 AOG (Aircraft on Ground) support for urgent needs. Standard, expedited, and overnight shipping options are available.