Durable Construction Wide links, skid plate, robust carbon plate, and sturdy pulley for extended lifespan Impact Protection Automatic Impact Recovery swiftly restores derailleur after impact SHIMANO SHADOW ES Slim, robust evolution of Shimano's chain-stabilizing SHADOW concept Accurate Wireless Shifting Wireless Di2 with HYPERGLIDE+ for smooth, immediate shifts Rock Strike Defense Wedge shape deflects impacts with Shimano's most durable derailleur design Secure Battery Sealed, secure, and removable battery stays in place during rough terrain Introducing the XTR M9250 long-cage derailleur, paired with a standard 10-51T M9200 cassette, offering riders and racers unmatched speed, range, and durability to conquer any mountain trail. Equipped with Automatic Impact Recovery, a robust design, and protected pulley solutions, this derailleur withstands harsh impacts while maintaining its swift shifting speed and superior performance.