Structural Flat Washer Flat Washer Type SAE Material Stainless Steel Material Grade/Class 316 Finish Plain For Screw Size #10 Inside Diameter 0.219 in Outside Diameter 1/2 in Maximum Thickness 0.9 in System of Measurement Inch Minimum Thickness 0.108 in Inside Diameter Tolerance +/-0.010 in Material Quality Standards ASTM A276 Outside Diameter Tolerance +/-0.010 in Pack Size Small Pack Resistance Properties Corrosion Resistant Saltwater Resistant Solvent Resistant