Sram x01 type 21 11 speed rear mechthanks to its horizontal parallelogram design x horizon can keep the chain gap the same across all 11 gears by taking vertical movement out of the equation this design doesnt just make shifting fasterit reduces shift force and eliminates ghost shifting features cage lockthe first rear derailleur of its kind sram type 21 lets you push your cage forward and lock it into place with the push of a button this creates slack removing all tension from t