Socket Head Cap Screw, Head Type Standard, System of Measurement Inch, Drive Type Socket, Drive Size 1/4 in, Material Alloy Steel, Material Grade/Class Class 12.9, Finish Black Oxide, Thread Size 5/16 In.-18, Minimum Thread Length 1 13/32 in, Fastener Length 3 1/4 in, Head Height 0.312 in, Head Diameter 0.469 in, Pack Size Small Pack, Thread Style Partially Threaded, Special Features Not Applicable, Countersink Angle Not Applicable, Manufacturer Location Made in US