SRAM GX 1x11 X-Horizon Rear DerailleurSRAM GX 1x11 X HORIZON REAR DERAILLEUR The Next Generation Of SRAM Leveraging the legendary history of SRAM shifting, the GX 2x11 rear derailleur provides incredible shifting speed and precision. X ACTUATION technology eliminates slop and shifting variation. ROLLER BEARING CLUTCH technology delivers maximum drivetrain stabilityeven through the most punishing terrain. And with CAGE LOCK technology, wheel removal and installation are easier than ever.