Made of bearing steel for durability and strength. Bearing type is miniature single row deep groove ball bearing, mainly take radial load as well as moderate axial load. Ball bearings are equipped with two rubber dust seals to prevent the ingress of dirt, and foreign matter. Bearing features: simple configuration, high speed, high precision, lower friction coefficient, less vibration and noise, most widely used. Miniature deep groove ball bearing suitable for all kinds of industrial equipment, micro motor, rotary motor, office equipment and so on. Product Name: Deep Groove Ball Bearing Material: Bearing Steel Color: Silver Model: 628RS Inner Diameter: 8mm />Outer Diameter: 24mm Thickness: 8mm Weight: 990g Package Contents: 60 pcs x Deep Groove Ball Bearing Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in a little different from the real thing. The measurement allowed error is +/- 1-3 cm.