1、RUBBER SEAL: These deep groove ball bearings have a double sided rubber seal to prevent impurities from entering and save lubricant 2、DURABLE MATERIAL: These ball bearings are made of excellent bearing steel. Steel structure makes it durable and does not deform under heavy loads 3、VARIOUS ADVANTAGES: Deep groove ball bearings have the advantages of low noise, fast heat dissipation, low friction, high speed, high temperature resistance and so on 4、WIDELY USED: Widely used in industrial machinery, motorcycles, automobiles, power tools and mechanical equipment and other fields 5、2PCS IN TOTAL: The package contain a total of 2pcs, enough for you to replace and use, very convenient 2 x Deep Groove Ball Bearing ​​Item Type: Deep Groove Ball BearingMaterial: Bearing steelInner Diameter x Outer Diameter x Thickness: Approx. 27 x 50 x 15mm / 1.06 x 1.97 x 0.59in