Flat Washer, Type B, Flat Washer Type Standard, Dimensional Standards ASME B18.22.1, Material Steel, Material Grade/Class Grade 2, Finish Zinc Plated, For Screw Size #1, Inside Diameter 1.062 in, Outside Diameter 3 in, Maximum Thickness 0.174 in, System of Measurement Inch, Minimum Thickness 0.146 in, Color Silver, Inside Diameter Tolerance +/-0.010 in, Outside Diameter Tolerance +/-0.010 in, Pack Size Small Pack, Rockwell Hardness B55, Thickness Tolerance -0.020 in/ +0.005 in