Fender Washer Flat Washer Type Oversized Dimensional Standards ASTM F844 Material Stainless Steel Material Grade/Class 18-8 Finish NL-19 For Screw Size 1/2 in Inside Diameter 0.531 in Outside Diameter 2 in Maximum Thickness 0.125 in System of Measurement Inch Minimum Thickness 0.125 in Color Silver Pack Size Small Pack Resistance Properties Corrosion Resistant Rockwell Hardness B70 Thickness Tolerance +/-0.015 in