Flat Washer Flat Washer Type Standard Dimensional Standards DIN 9021 Material Stainless Steel Material Grade/Class 316 Finish Plain For Screw Size M20 Inside Diameter 22 mm Outside Diameter 60 mm Maximum Thickness 4 mm System of Measurement Metric Minimum Thickness 4 mm Maximum Temperature 302 Degrees F Minimum Temperature -58 Degrees F Pack Size Small Pack Package Quantity 5