Hex Head Cap Screw Head Type Hex Diameter 1/4 In. Grade 9 Material Alloy Steel Finish Yellow Zinc Plated Thread Size 1/4-20 Thread Type Coarse Length under Head 3-1/2 In. Thread Length 3/4 In. Head Height 3/16 In. Head Width 7/16 In. Thread Style Partially Threaded Thread Direction Right Hand Proof Load 150 000 psi Tensile Strength 180 000 psi Rockwell Hardness C38 to C42 Meets/Exceeds ASME B18.2.1 ASTM F1941 FeZn5C Package Quantity 10