Flat Washer Flat Washer Type SAE Dimensional Standards ASME B18.21.1 Material Stainless Steel Material Grade/Class 316 Finish Plain For Screw Size 3/8 in Inside Diameter 0.406 in Outside Diameter 13/16 in Maximum Thickness 0.08 in System of Measurement Inch Minimum Thickness 0.051 in Color Silver Inside Diameter Tolerance +/-0.010 in Material Quality Standards ASTM A276 Outside Diameter Tolerance +/-0.010 in Pack Size Small Pack