Flat Washer Flat Washer Type Standard Dimensional Standards TCMA Material Stainless Steel Material Grade/Class 18-8 Finish Plain For Screw Size 5/8 in Inside Diameter 0.656 in Outside Diameter 1 3/8 in Maximum Thickness 0.141 in System of Measurement Inch Minimum Thickness 0.109 in Color Silver Maximum Temperature 750 Degrees F Rockwell Hardness B97 Thickness Tolerance +/-1/64 in Package Quantity 25