SRAM Force 22 WiFli Rear Derailleur - 11 Speed Medium Cage Black Model=Airstream Seatpost Taillight The balls are held in

The balls are held in place by a reinforced polyamide cage

Tool compartment

and suitable for trunk or hitch mounted bike racks

Dyna-Sys11 HG-X11 11-speed chain compatible

SRAM Force 22 WiFli Rear Derailleur - 11 Speed Medium Cage Black Model=Airstream Seatpost Taillight The balls are held inSRAM Force 22 WiFli Rear Derailleur 11 Speed Medium Cage Black. Competition grade rear derailleur with carbon and magnesium to keep weight low. Designed for easy to set up and adjustment. Carbon fiber and aluminum construction Cartridge bearing pulleys Stainless Steel hardware TECH SPECS Rear Derailleur Mount Type 10x1 Standard Rear Der Shifter Compatibility SRAM Exact Actuation Cage Length Medium Drivetrain Speeds 11 Weight 186 Color Black Chain Wrap