Flange Bolts Basic Material Steel Material Grade Alloy Steel Fastener Finish Plain 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 Partially Threaded Fastener Industry Standards ASTM A574 IFI-115 Thread Length 1 1/4 in Head Height 5/16 in Head Width 5/16 in Flange Dia 15/32 in Proof Load 140 000 psi Tensile Strength 170 000 psi Rockwell Hardness HRC37 Package Quantity 50