Flat Washer Flat Washer Type USS Dimensional Standards ASME B18.22.1 Material Steel Material Grade/Class Grade 2 Finish Black Oxide For Screw Size 2 1/4 in Inside Diameter 2.25 in Outside Diameter 4 3/4 in Maximum Thickness 0.22 in System of Measurement Inch Minimum Thickness 0.22 in Color Clear Inside Diameter Tolerance 2.365-2.42 Made in North America No Manufacturer Location Globally Sourced Material Quality Standards Not Rated Maximum Temperature 350 Degrees C