Radial Ball Bearing Bearing Industry Number 6304 Bore Diameter 20 mm Closure Double Sealed For Environment Oily/Greasy Outer Ring Width 15 mm Outside Diameter 52 mm Ring Material Alloy Steel Seal Type Contact System of Measurement Metric Cage Material Steel ABEC Rating 1 Ball Material Alloy Steel Ball Material Grade AISI 52100 Bore Diameter Tolerance +0/-0.1 mm Dynamic Radial Load Capacity 3 580 lbf Includes Retaining Ring No Lubricant Material Polyrex EM