Hex Head Cap Screw System of Measurement Inch Basic Material Steel Material Grade Grade 5 Fastener Finish Zinc Plated Dia./Thread Size 9/16 In.-18 Fastener Length 3 1/2 in Fastener Thread Direction Right Hand Fastener Thread Type UNF (Fine) Fastener Thread Style Partially Threaded Fastener Industry Standards ASME B18.2.1 Head Type Hex Min Thread Length 1 3/8 in Head Height 23/64 in Head Width 13/16 in Package Quantity 10