Optimized for impact survivability, the 12-speed mid-cage M9250 rear derailleur is the choice for both Shimano’s top enduro athletes and weight-conscious XC racers alike, especially when matched with the 9-45 compact cassette. Featuring all-new wireless Di2 shifting, Automatic Impact Recovery, a redesigned wedge shape and 23 mm of additional ground clearance for a bash-free ride, this rear derailleur stands out for the speed of its shift and its ability to keep riders competitive on the trail.