Shimano XT RD-M8000 Rear Derailleurs FEATURES: 46 tooth maximum rear cog for 1x11, 42 tooth maximum for 2x11 Low profile derailleur cage reduces collection of debris and potential for damage Shadow clutch reduces chain slap and dropped chains, on-off switch allows for simple wheel changes Externally adjustable clutch for easier spring tension adjustment Optimized slant angle lowers shift effort while improving shifting and driving stability SPECS: Largest Cog: 46 Rear Derailleur Mount Type: 10x1 Standard , Shimano Rear Direct Mount Chain Wrap Capacity (teeth): 47 Cage Length: Long Rear Der/Shifter Compatibility: Shimano Mountain Drivetrain Speeds: 11 Weight: 275g