Sram: MAXIMUM IMPACTWith its horizontal parallelogram design & 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 & eliminates ghost shifting. ROLLER BEARING CLUTCH technology reduces bounce & chain slap. CAGE LOCK technology makes wheel removal & installation easier than ever before. Paired with the XX1 shifter, the X-HORIZON RD forms the backbone of X-ACTUATION technology for unbelievably smooth shifting action.