Takes place of the rear wheel providing tension on the chain to protect the frame when rear wheel is removed for cleaning, storage, or transportAllows full forward or backward rotation of drivetrain and shifting through full range of gearsQuick and easy one-handed installation on standard QR style dropouts and removable pulley wheel works directly on 12mm thru axlesProfessional grade stainless-steel, aluminum, and solvent resistant plastic components ready for daily life in the wash bucketChain KeeperBlack/Yellow6400565UPC/EAN/GTIN: 790983297497