DESC: A performance purebred, the SRAM X0 10-speed rear derailleur handles your all-around, all-conditions mountain bike shifting needs. Constructed out of tough forged aluminum and features a carbon fiber/alloy cage for weight savings; pulleys boast sealed cartridge bearings for lasting use. Exact Actuation design takes the 1:1 actuation ratio of cable travel/derailleur movement and optimizes it for easy, dependable setup and 10-speed application. Direct cable routing reduces the amount of friction for enhanced shifting performance. Compatible with 36-tooth cassettes. Medium cage length is designed for use with 2 x 10-speed systems.