Lock Washer, Lock Washer Type Internal Tooth Lock, Finish Black Oxide, Material Steel, For Screw Size 5/8 in, Inside Diameter 0.64 in, Outside Diameter 1.1 in, Maximum Thickness 0.059 in, Dimensional Standards ASME B18.21.1, Material Grade/Class Not Graded, Pack Size Small Pack, Rockwell Hardness C40 to C50, System of Measurement Inch, Package Quantity 10