5/16-18 x 5/8" Socket Cap Screw - Steel - Black Oxide - UNC - Pkg of 100 - USA - Holo-Krome 72122

Socket head cap screws are ideal for precision work with close tolerances and applications needing a well tooled appearance. socket head cap screws supply greater tensile strength than equivalent hex head caps screws, while requiring less surface area to counterbore. thermal black oxide finish features a standard heat treatment finish which includes light drying oil; chemical black oxide is a chemical treatment plus rust resistant with no drying oil.