Machine Screw, Head Type Flat, Material Steel, Finish Zinc Plated, Drive Phillips, Thread Size 5/16 In.-18, Fastener Length 2 in, Head Width 0.579 in, Head Height 0.597 in, Drive Size #4, Tensile Strength 60,000 psi, Dimensional Standards ASME B18.6.3, Pack Size Bulk, Minimum Thread Length Not Applicable, Type Standard Machine Screw, Washer Outside Diameter Not Applicable, Washer Thickness Not Applicable, Maximum Head Width 0.579 in, Minimum Head Width 0.556 in, Maximum Head Height 0.597 in