Feature:1. Made of high strength steel and adopts hardening technology, which has greater wear resistance, durability, high temperature resistance, corrosion resistance, rust prevention and no deformation2. Through the special tooth shape and inclination, it provides fast and accurate indexing conversion function, which is better compatible with the speed change chains of various brands3. The hollow out design can easily reduce the weight and riding burden, achieve a good balance between strength and weight, easy to install and use, and there is no need to adjust the transmission system4. The old or damaged flywheel can be replaced directly. The unique mountain bike chain design can well control the speed change function5. The small teeth of the bicycle clip flywheel are often used in the process of use. The independent small teeth design is convenient for future replacement and maintenanceSpecification:Item Type: Bike FreewheelMaterial: High Strength SteelSpeed: 11 SpeedNumber of Gearwheel Teeth: 11-13-15-17-19-21-24-28-32-36-40T Package List:1 x Bike Freewheel2 x Gear Ring1 x Lock Ring