Sram: ACTION HEROThanks to its "horizontal parallelogram" design, the X-HORIZON rear derailleur can keep the chain gap the same across all 11 gears. By eliminating vertical movement, this design not only makes shifting faster but also reduces shift force and eliminates ghost shifting. The ROLLER BEARING CLUTCH technology reduces bounce and chain slap, while the CAGE LOCK technology makes wheel removal and installation easier than ever before.When paired with the X01 shifter, the X-HORIZON rear derailleur forms the backbone of X-ACTUATION technology, ensuring totally smooth shifting action.Please note that the main product title, 'X01 REAR DERAILLEUR TYPE 21 11 SPEED 11 SPEED', is not mentioned in the description as it may contain unnecessary information for SEO purposes. Likewise, the brand name, 'Sram', is not mentioned again.