Feature: 1. High strength once molding plastic steel material manufacturing, firm and durable. 2. High quality wear resistant plastic guide wheel, quiet and smooth, can effectively reduce chain damage. 3. Stable and accurate speed change, good compatibility, fit for all kinds of speed change models. 4. Light in weight and small in size, portable and will not bring burden to your bicycle, provide better use feeling. 5. Easy to install and operate, only need a few steps, can effectively save your time. Specification: Item Type: Bicycle Rear Derailleur Material: Plastic Steel Main Material, Steel Guide Plate, Plastic Guide Wheel Weight: Approx. 257g9.1oz Color: Black Applicable Installation Method: Straight Mounting Type (the frame needs a rear tail hook) Total Amount of Tooth Change:45 Teeth . Package List: 1 x Bicycle Rear DerailleurHigh strength once molding plastic steel material manufacturing, firm and durable. High quality wear resistant plastic guide wheel, quiet and smooth, can effectively reduce chain damage. Stable and accurate speed change, good compatibility, fit for all kinds of speed change models. Light in weight and small in size, portable and will not bring burden to your bicycle, provide better use feeling. Easy to install and operate, only need a few steps, can effectively save your time.