The Shimano Di2 XTR M9250 wireless long cage derailleur paired with a standard 10-51t M9200 cassette (cassette sold separately) gives riders and racers the speed, range, and robustness to tackle every trail on the mountain. With built-in Automatic Crash Recovery, an impact-deflecting shape, and simple covered-pulley solutions, this derailleur stands up to harsh trail impacts and still retains its lightning-quick shifting speed and top-level performance Wireless Di2 paired with HYPERGLIDE+ technology result in smooth, precise and instantaneous shifts Wide link structure, skid-plate design, durable carbon plate and solid pulley add robustness and longevity Automatic Impact Recovery function instantly returns the derailleur motor to its original position after impact .
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