Retaining Ring, System of Measurement Metric, Location Style External, Thickness 1.2 mm, Fits Shaft Diameter 21 mm, For Bore Diameter Not Applicable, Fits Groove Diameter 20 mm, Fits Groove Width 1.3 mm, Fits Groove Depth 0.5 mm, Free Inside Diameter 19.5 mm, Free Outside Diameter Not Applicable, Clearance Diameter Not Applicable, Material Spring Steel, Finish Zinc Plated, Material Grade/Class 1060-1090, Tensile Strength Not Applicable, Ring Type External Retaining Ring