Wedge Lock Washer, Lock Washer Type Wedge Lock, Finish Delta Protect, Material Steel, For Screw Size 5/16 in, Inside Diameter 0.34 in, Outside Diameter 0.53 in, Assembly Thickness 0.1 in, Assembly Thickness Tolerance +/-0.01 in, Color Silver, Dimensional Standards DIN 25201, Material Grade/Class Not Graded, Pack Size Small Pack, Rockwell Hardness HRC46, System of Measurement Metric, Package Quantity 20