Square Head Bolt Square Head Bolt Inch Steel Fastener Finish Zinc Yellow Material Grade Class 5 Dia/Thread Size 3/8 In.-16 Fastener Length 1 in Fastener Thread Direction Right Hand Fastener Thread Type UNC (Coarse) ASME B18.2.1 SAE J429 Head Height 1/4 in Head Width 9/16 in Flange Dia 3/8 in Thread Style Fully Threaded Rockwell Hardness HRC25 Head Type Square Head Package Quantity 50