5/16"-18 x 1-1/2" ASTM F593 18-8 Stainless Steel Hex Cap Screw / THREAD CLASS: 2A THREAD DIRECTION: RIGHT-HAND THREAD LENGTH: 0.875 INCHES NOMINAL FASTENER LENGTH: 1.500 INCHES NOMINAL HEAD STYLE: C1 HEXAGON HEAD HEIGHT: 0.195 INCHES MINIMUM AND 0.211 INCHES MAXIMUM WIDTH BETWEEN FLATS: 0.489 INCHES MINIMUM AND 0.500 INCHES MAXIMUM END ITEM IDENTIFICATION: 4220-01-617-9406 NOMINAL THREAD DIAMETER: 0.312 INCHES THREAD QUANTITY PER INCH: 18 PART NAME ASSIGNED BY CONTROLLING AGENCY: HEX CAP SCREW MATERIAL: STEEL COMP 304 OVERALL THREAD SERIES DESIGNATOR: UNC