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.Key Features:EXACT ACTUATION™ for fast and accurate shifts using SRAM\'s 1:1® actuation ratio (shifter cable travel: derailleur movement),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,A dedicated SRAM 1x™ rear derailleur.