Flange Bolts, Basic Material Steel, Material Grade Alloy Steel, Fastener Finish Plain, Dia./Thread Size 1/4 In.-20, Fastener Length 1 1/2 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 in, Head Height 17/64 in, Head Width 1/4 in, Flange Dia. 3/8 in, Proof Load 140,000 psi, Tensile Strength 170,000 psi, Rockwell Hardness HRC37, Package Quantity 50