Tapping Sheet Metal Screw Head Type Hex Washer Finish Zinc Plated Material Steel Screw Size 5/16 in Fastener Length 1 1/2 in Head Width 0.579 in Head Height 0.23 in Dimensional Standards ASME B18.6.3 Pack Size Small Minimum Head Width 0.556 in Maximum Head Width 0.579 in System of Measurement Inch Drive Slotted Package Quantity 100