USS Washer, Flat Washer Type USS, Dimensional Standards ASME B18.21.1, Material Steel, Material Grade/Class Case Hardened, Finish Zinc-Plated, For Screw Size 1 3/8 in, Inside Diameter 1.5 in, Outside Diameter 3 1/4 in, Maximum Thickness 7/32 in, System of Measurement Inch, Minimum Thickness 5/32 in, Color Silver, Inside Diameter Tolerance 1.43-1.545, Made in North America Not Made in North America, Manufacturer Location Globally Sourced, Material Quality Standards Not Rated