1、IRON MATERIAL: The freewheel is made of premium iron material, which is oil resistant, long lasting and reliable and durable. It can withstand long time use and high strength riding, not easy to be damaged and keep its good function and performance. 2、EXCELLENT CRAFTSMANSHIP: Made through exquisite craftsmanship, the freewheel is durable and won't deform over time, providing you with a smooth and reliable using experience. 3、EASY INSTALLATION: The freewheel comes with an adapter that makes installation easier and more convenient for professional bike mechanics and DIY enthusiasts. 4、GEAR SELECTION: The set contains two kinds of freewheels, 22 teeth and 24 teeth, which can meet different installation needs, you can choose according to your needs. 5、MODIFICATION KIT: Whether you want to upgrade the performance of your original bike or make customized modifications, this kit can meet your needs. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.