A dedicated SRAM 1x� rear derailleur 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� controls chain tension for consistent shifting By eliminating unwanted chain movement, X-horizon� shifts faster, reducing shift effort and chain slap Cage Lock� technology makes for fast wheel changes or chain installation Rival 1 11sp 36 Mid 1 to 1 BLKUPC/EAN/GTIN: 710845807862