Split Lock Washer Lock Washer Type Split Lock Finish Black Oxide Material Steel For Screw Size 1 5/8 in Inside Diameter 1.633 in Outside Diameter 2.553 in Maximum Thickness 0.359 in Minimum Thickness 0.359 in Dimensional Standards ASME B18.21.1 Material Grade/Class Not Graded Pack Size Small Pack Rockwell Hardness C40 to C50 Package Quantity 5