SRAM X01 11-Speed Rear Derailleur, Black

With its "horizontal parallelogram" design and pulley offset, X-HORIZON keeps the chain gap constant across all 11 gears, providing fast, precise shifts. By limiting all movement to the horizontal axis, this design is faster, reduces shift force and eliminates ghost shifting. ROLLER BEARING CLUTCH technology reduces bounce and chain slap. CAGE LOCK technology makes wheel removal and installation easier than ever before. Paired with the X01 shifter, the X-HORIZON RD forms the backbone of X-ACTUATION technology for unbelievably smooth shifting action.