Large O.D. Oversized Washer, Flat Washer Type Oversized, Dimensional Standards AMPG 2001 FL.05, Material Steel, Material Grade/Class Case Hardened, Finish Zinc-Plated, For Screw Size 3/8 in, Inside Diameter 0.406 in, Outside Diameter 2 in, Maximum Thickness 5/64 in, System of Measurement Inch, Minimum Thickness 3/64 in, Color Silver, Inside Diameter Tolerance +/-0.010 in, Material Quality Standards ASTM A108, Outside Diameter Tolerance +/-0.010 in, Pack Size Small Pack, Rockwell Hardness B55