Premium Quality --- This 428 9T sprocket is made of high quality steel material, which is wear resistant and durable to use. It is not easy to break, has reliable quality and ensures high hardness for long term use. Fine Workmanship --- The 9 tooth sprocket adopts professional manufacturing with stable characteristics and high reliability, which is a great accessory for electric scooter. Scope of Applications --- The 428-9T Front Sprocket is special designed for electric scooter, 17 x 12mm / 0.7 x 0.5in of the inner diameter size. Easy to Install --- The motorcycle Sprocket is easy to install and disassemble, which is a wonderful replacement for your old or broken one, directly fitment. Product Specification --- Item type: 9T chain sprocket; material: steel; inner diameter size: approx. 17 x 12mm / 0.7 x 0.5in; electric scooter accessory. Product Quantity: 1 Piece Product color: black Product size: inner diameter 17mm