Feature:1. Made of steel, wear resistance, high temperature resistance, corrosion resistance, rust resistance, no deformation, good impact resistance.2. Hollow design can easily reduce weight and riding burden, achieve a good balance between strength and weight, easy to install and use.3. The special high‑precise tooth and slope provide fast and accurate conversion function, with stable gears and precise positioning in the 8‑speed range.4. The small teeth of cassette flywheel are often used, and the independent small tooth design is convenient for future replacement and maintenance.5. Easy to install without adjustment, great replacement for old or damaged flywheels of mountain bikes and road bikes.Specification:Item Type: Cassette FlywheelMaterial: SteelColor: As Picture ShownWeight: Approx. 288.0g/10.2ozSpeed: 8 SpeedTeeth: 11‑13‑15‑17‑19‑21‑24‑28T Package List:1 x Cassette Flywheel2 x Flywheel Teeth Ring1 x Locking Ring