Polymer SBR20UU 20mm Low noise Linear Motion Ball Bearing Pillow BlockPolymer SBR20UU 20mm Low noise Linear Motion Ball Bearing Pillow Block Polymer SBR20UU 20mm Linear Motion Ball Bearing Pillow Block. New solid polymer material, lightweight, good wear resistance and strength, more stable and help to reduce noise Item: Solid Polymer SBR20UU Bearing Type: Linear Ball Bushing Inner Contact Diameter: 20mm Improve them efficiency and save energy. Quantity: One Bearing No oil needed,Self lubricating, Dust proof. Improve