This item will be shipped within One Week Returns Subject to 15% restocking Fee SSER-55mm Stainless Steel Insert Ball Bearing 55mm Inner Diameter SSER-55mm Stainless Steel Insert Ball Bearing, bearing is set screw locking, bearing is wide inner ring with cylindrical outer ring and snap ring, bearing is relubrication groove with oil hole on set screw side, bearing is anti-rotation pin on side opposite grease groove, bearing is supplied with water/wash resistant.