Flat Washer, Flat Washer Type Standard, Dimensional Standards ASME B18.22.1, Material Steel, Finish Zinc-Plated, For Screw Size 1/2 in, Inside Diameter 0.531 in, Outside Diameter 1 1/4 in, Maximum Thickness 7/64 in, System of Measurement Inch, Minimum Thickness 7/64 in, Color Silver, Inside Diameter Tolerance 0.526-0.546, Made in North America Not Made in North America, Manufacturer Location Globally Sourced, Material Quality Standards Not Rated, Maximum Temperature 350 Degrees C