11 speed 105 wide link rear derailleur medium cage gs short cage ss advanced wide link design increases rigidity and shifting performance super stiff for fast and accurate changes across the cassette large 11 tooth pulleys increase service life and reduce noise super light shift action compatible with 11 speed drivetrainsmedium cage gs maximum low sprocket 28 32t with double chainsetmaximum front difference 16t total capacity 37taverage weight 232 gramsshort cage ssmaximum lo