1、It is made of steel material which makes it durable and resistant to deformity under heavy loads. This bearing is brand new and pre-lubricated/greased from the manufacturer so no additional lubrication is required. 2、This v groove ball bearing is for use in applications that involve combined radial and axial loads and a need for high running accuracy at high rotational speeds. 3、Rolling bearings use rolling elements to maintain the separation between moving parts to reduce rotational friction and support radial and axial loads. 4、Exquisite mechanical design makes little noise when rotating. 5、The design of V-groove is very practical. Feature: It is made of steel material which makes it durable and resistant to deformity under heavy loads. This bearing is brand new and pre-lubricated/greased from the manufacturer so no additional lubrication is required. This v groove ball bearing is for use in applications that involve combined radial and axial loads and a need for high running accuracy at high rotational speeds. Rolling bearings use rolling elements to maintain the separation between moving parts to reduce rotational friction and support radial and axial loads. Exquisite mechanical design makes little noise when rotating. The design of V-groove is very practical. Specification: Model: V623ZZ Inner diameter: 3mm Outer diameter: 12mm Thickness: 4mm Bearing material: Bearing steel Use characteristics: High speed Rolling body series: Single row Raceway type: Spherical Package list: 10 * Ball Bearings Note: The actual product color may deviate from the photo due to light. There may be a slight deviation in the measurement of product.