Description:Main parts:Aluminum housing + LM .UU linear ball bearingsMain application:working with linear rails.The universal Ball Bearings is great for you to replace the damaged Ball Bearings in your devices to improve them efficiency and save energy. Widely used in home appliances, industrial, low noise and high speed electric motors, construction machinery, automotive components, pumps, and machinery. Smooth moving, low friction, high rigidity and long life. Economical, easy to maintain replace.Features:Model: SC8UUShaft ID: 8mmInner Diameter: 8mmMain application:working with linear rails.Main parts:Aluminum housing + LM .UU linear ball bearingsPacking list :1PC SCS8UU bearing