Split Lock Washer Finish Zinc Plated Material Steel For Screw Size 9/16 in Inside Diameter 0.564 in Outside Diameter 0.975 in Maximum Thickness 0.17 in Minimum Thickness 0.17 in Color Silver Dimensional Standards ASME B18.21.1 Material Grade/Class Not Graded Pack Size Small Pack Rockwell Hardness C38 System of Measurement Inch Thickness Tolerance +0.010 in Package Quantity 50