Usage Tips:HIGH QUALITY: Made of high quality bearing metal, with the resistance of wear and collision.FEATURE: It is characterized by small frictional resistance and high rotational speed and can be used on mechanical parts that are subjected to radial loads or axial loads, such as machine tool, electronic equipment, .GOOD DESIGN: Exquisite design, two sides metal sealed ball bearing, with good dustproof effect. Built-in precise Mini bearing provides smooth running and long service life.APPLICATION: Standardization size, used for machine tool, electronic equipment, pump industry, plastic machine, motor and more.size:15x28x7mmMaterial:metalcolour:Black + SilverPackage Contents:10 x Bicycle hub bearingOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.