Air Force-Navy AN310-8 Castle Nuts comply to spec QQ-P-416, Type 2, Class 3 and are constructed of steel with a cadmium surface treatment. Castellated or Castle nuts are used with drilled-shank bolts, clevis bolts, eye bolts and studs. The bolt or axle has one or two holes drilled through its threaded end. The nut is torqued properly and then, if the slot isn't aligned with the hole in the fastener, the nut is rotated to the nearest slot. The nut is then secured with a cotter pin or safety wire.
Thread Class: 3B
Thread Direction: Right-Hand
Nut Style: Castellated, Hexagon
Nut Height: 0.546 Inches Minimum And 0.578 Inches Maximum
Width Across Flats: 0.738 Inches Minimum And 0.752 Inches Maximum
Thread Series: Unf
Thread Quantity Per Inch: 20
Nominal Thread Size: 0.500 Inches
Bearing Surface Type: Chamfered Or Washer Faced
Material: Steel Overall
Surface Treatment: Cadmium Overall
Surface Treatment Document And Classification: Qq-P-416 Ty 2 Cl 3 Fed Spec Single Treatment Response Overall