Flat Washer Flat Washer Type USS Dimensional Standards ASME B18.21.1 Material Steel Material Grade/Class Grade 2 Finish Hot Dipped Galvanized For Screw Size 1 in Inside Diameter 1 in Outside Diameter 2 1/2 in Maximum Thickness 0.165 in System of Measurement Inch Minimum Thickness 0.165 in Color Silver Inside Diameter Tolerance 1.055-1.092 Made in North America No Manufacturer Location Globally Sourced Material Quality Standards Not Rated Maximum Temperature 350 Degrees C