Structural Flat Washer Flat Washer Type Standard Material Steel Material Grade/Class Grade 2 Finish Hot Dipped Galvanized For Screw Size 5/8 in Inside Diameter 0.172 in Outside Diameter 1 5/16 in Maximum Thickness 0.177 in System of Measurement Inch Minimum Thickness 0.122 in Material Quality Standards ASTM F436 Pack Size Bulk Pack Rockwell Hardness HRC26 RoHS Compliant No Thickness Tolerance 0.122 to 0.177 in Package Quantity 1000