Hex Head Cap Screw System of Measurement Inch Basic Material Steel Material Grade Grade 5 Fastener Finish Zinc Plated Dia./Thread Size 5/16 In.-18 Fastener Length 2 1/4 in Fastener Thread Direction Right Hand Fastener Thread Type UNC (Coarse) Fastener Thread Style Fully Threaded Fastener Industry Standards ASME B18.2.1 Head Type Hex Head Height 7/32 in Head Width 1/2 in Package Quantity 50