Thick Washer Flat Washer Type Standard Dimensional Standards AMPG 2001 FL.06 Material Steel Material Grade/Class Grade 8 Finish Zinc Yellow For Screw Size 5/8 in Inside Diameter 0.656 in Outside Diameter 1 5/16 in Maximum Thickness 0.229 in System of Measurement Inch Minimum Thickness 0.206 in Color Yellow Inside Diameter Tolerance +/-0.010 in Outside Diameter Tolerance +/-0.010 in Pack Size Small Pack Rockwell Hardness C43 Thickness Tolerance +0.005/-0.020 in