Bicycle Rear Derailleur Hanger, Rear Derailleur Adapter, Bicycle Drivetrain Protection Frame, Bicycle Rear Derailleur Accessories 1. The hanger is an accessory of the frame (except for the claw-type rear derailleur) and has nothing to do with shifting and the rear derailleur. 2. Most hangers are made of 6061 aluminum alloy. Why not use steel? 3. When you accidentally crash, you may hit the derailleur, causing it to deform and affecting the drivetrain function. 4. The rear hanger is made of aluminum alloy, allowing a certain degree of deformation to protect the derailleur from damage. 5. In case of severe颠簸, the rear hanger can break and then be replaced with a new one, thus reducing the maintenance cost of the frame. 6. Steel is too strong to provide protection. Specification Parameters: 1. Upgrade or replace the rear derailleur claw; it is stronger and harder to improve shifting performance. 2. It is precision-machined from solid 6061 aluminum via CNC with precise tolerances. 3. It is stronger than any device hanger and can improve shifting performance. 4. It will break before the frame is damaged to fulfill its main function. 5. All hangers come with instructions and hardware. 6. It can be directly replaced on the device to ensure compatibility. 7. Model: A01 Mountain and Road Bicycle Rear Derailleur Protector Bracket Protect your rear derailleur from any damage.