Features1Iron Material: Flywheel is made of iron material, which is oil resistant and has a long service life with reliable and durable performance. 2Durable Design: With its exquisite craftsmanship, the flywheel is durable and will not deform over time, maintaining its function and performance. 3Easy to Install: The flywheel with adapter is easy to install, convenient for professional bike mechanics and DIY enthusiasts. 4Enhance Your Bike Performance: The 25.526mm flywheel adapter and 20T flywheel kit is designed to improve your bike's performance with its iron material and reliable durability. 5Versatile Compatibility: With its size of approximately 25.526mm, this flywheel kit is compatible with a wide range of electric bikes.SpecificationItem Type: Freewheel Adapter KitMaterial: IronPackage List1 x Freewheel Adapter1 x Freewheel