External Grip Ring System of Measurement Inch Location Style External Thickness 0.05 in Fits Shaft Diameter 1/2 in For Bore Diameter Not Applicable Fits Groove Diameter 0.478 in Fits Groove Width 0.056 in Fits Groove Depth 0.011 in Free Inside Diameter 0.47 in Free Outside Diameter Not Applicable Clearance Diameter Not Applicable Material Steel Material Grade/Class Not Graded Tensile Strength Not Applicable Ring Type External Grip Ring Thickness Tolerance +/-0.003 in