Push On Cap Nut,0.018 In. Thk,PK100, System of Measurement Inch, Location Style External, Thickness 0.018 in, Fits Shaft Diameter 1/4 in, For Bore Diameter 1/4 in, Fits Groove Diameter Not Applicable, Fits Groove Width Not Applicable, Fits Groove Depth 0.2031 in, Free Inside Diameter 0.289 in, Free Outside Diameter 0.5 in, Clearance Diameter Not Applicable, Material Spring Steel, Finish Zinc Plated, Material Grade/Class SAE 1050-1065, Tensile Strength Not Applicable