Flat Washer Flat Washer Type Standard Dimensional Standards DIN 125-1A Material Steel Material Grade/Class Class 8.8 Finish Zinc Plated For Screw Size M10 Inside Diameter 10.5 mm Outside Diameter 20 mm Maximum Thickness 2 mm System of Measurement Metric Minimum Thickness 2 mm Color Silver Inside Diameter Tolerance 0.413-0.424 Made in North America No Manufacturer Location Globally Sourced Material Quality Standards ASTM A-325 Maximum Temperature 350 Degrees C