USS Washer Flat Washer Type USS Dimensional Standards ASME B18.22.1 Material Steel Material Grade/Class Class 10.9 Finish Zinc Yellow For Screw Size 1/4 in Inside Diameter 0.313 in Outside Diameter 47/64 in Maximum Thickness 0.065 in System of Measurement Inch Minimum Thickness 0.065 in Color Yellow Inside Diameter Tolerance 0.307-0.327 Made in North America No Manufacturer Location Globally Sourced Material Quality Standards ASTM A-325 Maximum Temperature 350 Degrees C