Welcome to ZTTO Official Store! Item Name: Bicycle Flywheel Material:Steel Gear Ratio: 11-13-16-20-24-28-34-40T Size:15.5cmx15.5cmx6cm/6.1inx6.1inx2.36in Description: The gear sprocket is specially designed for mountain bikes, which can control the speed change function well. Strong oxidation resistance makes it difficult to rust and has a long service life. Because of the hollow design, the weight is reduced and there is no additional problem on the bicycle. This product is strong, durable and wear-resistant. Made of steel material, the bicycle flywheel is durable. The length of the product is 15.5cm, the width is 15.5cm, and the thickness is 6cm. It is suitable for mountain bikes. Notes: Due to the light and screen setting difference, the product's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 X Bicycle Flywheel