If you expect every bit as much out of your equipment as you expect out of yourself, then XTR is the answer. Shimano's XTR Shadow Rear Derailleur comes to the game with super-light, cold forged-aluminum and carbon construction. It's strong spring keeps the body stable even when you're blasting through rough sections. The famously smooth, linear feel delivers precise shifts every time no matter what gear you're in. Plus, the Shadow design of this derailleur features direct cable routing while its low profile barely protrudes past the quick-release nut. These features mean there's much less risk of striking and damaging the derailleur or snagging the cable on roots or rocks.