The SRAM Force 1 rear derailleur adopts all the technologies of SRAM 1x� MTB to provide the fastest, quietest 1x11 shifting available SRAM�s unique clutch system eliminates chain slack, providing for smoother, quieter, and more secure chain travel Exact Actuation� for fast and accurate shifts using SRAM�s 1:1� actuation ratio X-sync� pulley features a 12-tooth design that helps control the chain`s lateral movement ROLLER BEARING CLUTCH�`s one-way roller clutch controls chain tension for consistent shifting X-Horizon� straight parallelogram design limits all movement to the horizontal axis, which makes ghost shifting impossible while also reducing shift force Cage Lock� technology makes for fast wheel changes or chain installation Sram Road 10- and 11-speed compatible Force 1 11sp 42 Long 1to1 GreyUPC/EAN/GTIN: 710845807855