SRAM GX Eagle 12-Speed Rear Mech. The SRAM GX Eagle 12-Speed Rear Mech benefits from SRAM’s redesigned Type 3.0 Roller Bearing Clutch. It has a smooth shifting curve and provides precise, consistent and quiet drivetrain performance, thanks to trickle down technology from higher end Eagle drivetrain models. X-Actuation and X-Horizon technologies ensure ghost shifting and random jumps between the cassette cogs are a thing of the past Features: Material: Aluminium (cage), Steel (spring, pulley), Stainless Steel (hardware)Max Tooth: 50TCompatibility: All Eagle drivetrainsWeight: 290gTechnologies: Cage Lock: With Cage Lock technology in the rear derailleur, wheel removal and installation, as well as chain installation, becomes faster and simpler. Just push the cage forward to create slack and lock it into placeRoller Bearing Clutch: The Roller Bearing Clutch delivers maximum drivetrain stability even through the most punishing terrain. This stability benefits the drivetrain dramatically, as derailleur bounce and chain slap are eliminated without sacrificing precisionX-Actuation: Developed specifically for SRAM 1x drivetrains, X-Actuation keeps shifting sharp and consistent across the entire cassette X-Horizon: The X-Horizon ‘straight parallelogram’ design limits all movement on the horizontal axis, which makes ghost shifting impossible while also reducing shift force. The large upper pulley offset design maintains a constant chain gap across all gears and guarantees faster and more exact shifting X-Sync: The X-Sync pulleys and chainrings tall square teeth edges engage the chain earlier than traditional triangle shaped teeth. To provide the best possible performance in muddy conditions, the X-Sync jockey wheels have been designed with mud-clearing recesses for the inner chain links and rollers. The X-Sync jockey wheels are an integral part of the SRAM 1x drivetrains exceptional performance and efficiency Buy SRAM Components from Chain Reaction Cycles, the World’s Largest Online Bike Store.