Flat Washer Flat Washer Type Standard Dimensional Standards DIN 125-1A Material Stainless Steel Material Grade/Class 18-8 Finish Plain For Screw Size M20 Inside Diameter 21 mm Outside Diameter 37 mm Maximum Thickness 3.3 mm System of Measurement Metric Minimum Thickness 2.7 mm Color Silver Inside Diameter Tolerance +0.33 mm Made in North America No Manufacturer Location Globally Sourced Maximum Temperature 302 Degrees F Minimum Temperature -58 Degrees F