Built to give us peak shifting performance in the worst conditions imaginable, the SRAM XS-1297 XX Eagle Transmission 12-Speed Cassette shifts better the harder we pedal, thanks to the full X-Sync design. Specifically engineered to optimize the new XX Eagle Transmission drivetrain, the cassette comes into direct contact with our derailleur ensuring perfect alignment and buttery-smooth shifting every time. The 10-52 tooth range gives us a gear for every grade, so we can keep our pedals spinning when the trail seems to go straight up.