Bopworx Detachable Rear Bicycle Derailleur Guard - Protects the Bike Rear Derailleur During Transport and Storage The Bopworx Bicycle Protection Rear Derailleur Guard is the best solution for protecting your rear derailleur and derailleur hanger during travel and storage of you bike. The stainless steel slide-on is designed for ease of use with bike wheel's quick release system, the derailleur guard covers your bicycle's rear derailleur with a reinforced plastic arm and semi-soft rubberized padding Bopworx Guards are designed to be easy to attach - simply open the bicycle wheel quick release, slide into position and close quick release to hold firmly in place. There is no need for additional tools or equipment to fix the Bopworx Guard, as the Guard has been designed to be simply to use by Cyclists for Cyclists. Designed to work with all types of Bicyle, but please note the Bopworx Rear Derailleur Guard is Not designed to work with rear through-axles