This item will be shipped within One Week Returns Subject to 15% restocking Fee RCR-16L Rubber Cartridge Ball Bearing Eccentric Locking Collar 1" Inch Inner Diameter RCR-16L conductive Rubber Cartridge Ball Bearing, it uses to dissipate static, it reduces noise ans vibration, RCR-16L commonly assembled in pressed steel housings, bearing is narrow inner ring, Standard seal is RST tight riding, full cover, and metal shroud seals.