Feature: 1. 428 9T Chain sprocket, easy and convenient for installation and disassemble. 2. Professional manufacturing, stable performance, high reliability, wonderful using experience. 3. Made of steel, high hardness, wear resistance and durable to use. 4. 9 Tooth sprocket, wonderful replacement for the old or broken one, directly fitment. 5. Special designed for electric scooter, 17 x 12mm / 0.7 x 0.5in of the inner diameter size. Specification: Condition: Item Type: 9T Chain Sprocket Material: Steel Inner Diameter Size: Approx. 17 x 12mm / 0.7 x 0.5in Electric scooter accessory Package List: 1 x 9T Chain Sprocket