The impact-resistant optimized 12-speed derailleur M8250 with a medium cage is the top choice for everyday trail riding. It offers unmatched durability, fast and precise gear shifts, and saves weight when combined with the 9-45T compact cassette. With the new wireless Di2 shifting, automatic shock absorption, a 500% gear range, and 23 millimeters of additional ground clearance for a smoother ride, the M8250 derailleur is designed to be relentlessly reliable so you can focus entirely on the trail.