Flat Washer Flat Washer Type Standard Dimensional Standards ASME B18.22.1 Material Stainless Steel Material Grade/Class 316 Finish Plain For Screw Size 5/16 in Inside Diameter 0.344 in Outside Diameter 11/16 in Maximum Thickness 0.063 in System of Measurement Inch Minimum Thickness 0.034 in Color Silver Inside Diameter Tolerance +0.015 in -0.005 in Made in North America No Manufacturer Location Globally Sourced Maximum Temperature 302 Degrees F