Flat Washer Flat Washer Type Standard Dimensional Standards DIN 125-1A Material Steel Material Grade/Class Grade 2 Finish Zinc Plated For Screw Size M39 Inside Diameter 40 mm Outside Diameter 72 mm Maximum Thickness 6 mm System of Measurement Metric Minimum Thickness 6 mm Color Silver Inside Diameter Tolerance 1.575-1.599 Made in North America No Manufacturer Location Globally Sourced Material Quality Standards Not Rated Maximum Temperature 350 Degrees C