6304Z 6304 Universal Fit 1 Shield Ball BearingOne New Aftermarket Replacement Single Shielded Deep Groove Ball Bearing 6304Z 6304 Universal Fit This 6304Z is a single shielded, single row deep groove ball bearing measuring 20 mm bore x 52 mm outside diameter x 15 mm width. The metal shield on one side protects internal components from contamination while keeping friction low, making it well suited for high speed rotation under combined radial and axial loads. This is a widely used metric bearing