Flat Washer Flat Washer Type Standard Dimensional Standards DIN 9021 Material Steel Material Grade/Class Grade 2 Finish Zinc Plated For Screw Size M27 Inside Diameter 28 mm Outside Diameter 50 mm Maximum Thickness 4 mm System of Measurement Metric Minimum Thickness 4 mm Color Silver Inside Diameter Tolerance 1.181-1.214 Made in North America No Manufacturer Location Globally Sourced Material Quality Standards Not Rated Maximum Temperature 350 Degrees C