AN4 Bolts (1/4-28)

AN4 hex head aircraft bolts, also referred to as aviation bolts, are designed for critical aerospace applications requiring high strength and reliability.

These bolts are manufactured from high-strength alloy steel, typically 4037 or 8740 (8740 being the most common). They are centerless ground for precision and threaded after heat treatment to ensure maximum structural integrity.

With a minimum tensile strength of 125,000 PSI, these aircraft bolts meet demanding aviation standards.

They are cadmium plated per QQ-P-416A, Type II, Class 3 for enhanced corrosion resistance.

Available configurations:
Drilled shank for cotter pin
Undrilled shank for stop nut applications (“A” suffix)
Drilled head for safety wire (“H” suffix)

The “C” designation indicates Type 431 stainless steel.

Dimensions:
Length measured from under the head to the end of the shank
Grip = unthreaded portion of the bolt
Multiple lengths available depending on application