1/4"-20 x 2-1/4" ASTM F593 18-8 Stainless Steel Hex Cap Screw / THREAD CLASS: 2A THREAD DIRECTION: RIGHT-HAND FASTENER LENGTH: 2.250 INCHES NOMINAL HEAD STYLE: C1 HEXAGON HEAD HEIGHT: 0.150 INCHES MINIMUM AND 0.163 INCHES MAXIMUM WIDTH BETWEEN FLATS: 0.428 INCHES MINIMUM AND 0.438 INCHES MAXIMUM NOMINAL THREAD DIAMETER: 0.250 INCHES THREAD QUANTITY PER INCH: 20 MATERIAL: STEEL CORROSION RESISTING OVERALL THREAD SERIES DESIGNATOR: UNC