Flat Washer, Flat Washer Type Standard, Dimensional Standards AMPG 2001 FL.06, Material Steel, Material Grade/Class Through Hardened, Finish Zinc Yellow, For Screw Size 1 3/8 in, Inside Diameter 1.438 in, Outside Diameter 2 3/4 in, Maximum Thickness 17/64 in, System of Measurement Inch, Minimum Thickness 15/64 in, Color Yellow, Inside Diameter Tolerance +/-0.010 in, Material Quality Standards ASTM A108, Outside Diameter Tolerance +/-0.010 in, Pack Size Small Pack, Rockwell Hardness C43