Carriage Bolt Inch Neck Type Square Basic Material Steel Material Grade Grade A Fastener Finish Plain Dia/Thread Size 5/16 In.-18 Fastener Length 2 in Fastener Thread Direction Right Hand Fastener Thread Type UNC (Coarse) ASME B18.5 SAE J429 Drill Size 21/64 in Head Dia 0.719 in Head Height 11/64 in Head Type Round Square Height 0.187 in Square Width 0.324 in Tensile Strength 74 000 psi For Use With Grade 2 Hex Nuts Package Quantity 100