USS Washer Flat Washer Type USS Dimensional Standards ASME B18.22.1 Material Steel Material Grade/Class Grade 2 Finish Black Oxide For Screw Size 5/8 in Inside Diameter 0.172 in Outside Diameter 1 3/4 in Maximum Thickness 0.141 in System of Measurement Inch Minimum Thickness 0.141 in Pack Size Small Pack Thickness Tolerance 0.108 to 0.160 in Package Quantity 650