Hex Head Cap Screw Head Type Hex Diameter 1 In. Grade 8 Material Alloy Steel Finish Plain Thread Size 8 Thread Type Coarse Length under Head 5 In. Thread Length 2-1/4 In. Head Height 39/64 In. Head Width 1 1/2 In. Thread Style Partially Threaded Thread Direction Right Hand Seal Material Alloy Steel Proof Load 120 000 psi Tensile Strength 150 000 psi Rockwell Hardness C33 to C39 Meets/Exceeds SAE J429 AND ASME B18.2.1