Feature:1. Steel Plate Material: Uses high tension steel plate with nickel plating and multi layer electroplating anti rust treatment, having good performance for long service.2. Fine Craft: High accuracy gear ratio makes gear shifting more fluent, also has hollow punching design to reduce dead weight, improving your using experience.3. Item Detail: Cassette cogs is 11‑12‑13‑15‑17‑19‑21‑23‑25‑28‑31‑34T, 12 speed type. Has strong compatibility for road bikes bicycles, can be used for most models.4. Fluent Running: Has fluent rotation without too much noise, having close connection with the bike hub, stable running for your satisfying riding feelings.5. Little Burden: Has a weight of 464g/16.4oz, the fluent gear will not increase riding burden or cause additional energy waste, but giving a better driving experience.Specification:Item Type: FreewheelMaterial: Nickel SteelColor: As Picture ShownApplication: For Road Bike, Folding BicycleGross Weight: Approx.464g/16.4ozSpeed Ratio: 12 Speed, 11-12-13-15-17-19-21-23-25-28-31-34T Package List:1 x Freewheel2 x Tooth Piece1 x Flywheel Lock Cover