Split Lock Washer Finish Black Oxide Material Steel For Screw Size 7/16 in Inside Diameter 0.44 in Outside Diameter 0.836 in Maximum Thickness 0.143 in Minimum Thickness 0.143 in Dimensional Standards ASME B18.21.1 Material Grade/Class Not Graded Pack Size Small Pack Rockwell Hardness C38 Package Quantity 25