1、[10PCS BALL BEARINGS] Including 10pcs rubber sealed ball bearings, sufficient in quantity, easy to use and replace. 2、[BEARING STEEL] Made of premium bearing steel, it has durability and resistance to deformation under heavy loads. 3、[RADIAL AND AXIAL] Deep groove ball bearings are mainly used to bear radial load, but also can bear certain axial load. 4、[FOR LINEAR MOTION] Medium load ball bearings have moderate speed, suitable for relatively stable linear motion equipment. 5、[STANDARD SIZE] These rubber sealed bearings have standard diameter and appropriate thickness for easy installation. 10 x Ball Bearings Item Type: Rubber Sealed Ball BearingMaterial: Bearing Steel Model Inner Diameter Outer Diameter Thickness 6300 10mm / 0.39in 35mm / 1.38in 11mm / 0.43in 6301 12mm / 0.47in 37mm / 1.46in 12mm / 0.47in 6302 15mm / 0.59in 42mm / 1.65in 13mm / 0.51in 6303 17mm / 0.67in 47mm / 1.85in 14mm / 0.55in 6304 20mm / 0.79in 52mm / 2.05in 15mm / 0.59in