Note: There are many specifications to choose from, please check the specifications you need carefully before purchasing. Choose the one which suits you best. (11-25T). Best choice: The bicycle flywheel is made of high quality steel, high temperature resistance, corrosion resistance, rust resistance, resistance to deformation , wear resistance, high durability, good impact performance, high precision of tooth shape, tooth shape design, strong compatibility, allowing you to ride in line is more likely Features : Provides fast and precise indexing shifting with special tooth profile and ramps, provides smooth speed in its 10-speed range, precise positioning Easy installation: professionally manufactured, direct replacement old or damaged flywheels. Great accessory for mountain bikes and road bikes. Easy installation, no need to adjust the transmission Compatibility: Sram and Shimano 10-speed system.