SRAM GX Rear Derailleur - 10 Speed, Medium Cage, BlackSRAM GX rear derailleur takes the place of X. 9 and X. 7 10 speed models and provides shifting speed and precision. Product Details: Exact Actuation technology eliminates slop and shifting variation Roller Bearing Clutch delivers maximum drivetrain stability even through the most punishing terrain Specifications: Cage Length: Medium Chain Wrap Capacity (teeth): 35 Color: Black Drivetrain Speeds: 10 Largest Cog: 36 Rear Der Shifter Compatibility: SRAM