Features1High Quality Material: It is made of high quality 6061T aviation aluminum. It is light, durable, not easy to wear and can be used for a long time. 2Ergonomic Design: The ergonomic shape makes use of the efficient function of trampling to create more trampling traction. 3Installation Method: The positive teeth correspond to the width of the chain teeth, and the negative teeth correspond to the narrow chain teeth. This is the drive motor chain adapter between for TSDZ2. You need to use your own compatible 104BCD chain. 4High Compatibility: The chainring adapter is a universal type. It can be equipped with 34T/36T/38T/48T and other chainwheel after use. 5Fine Workmanship: Manufactured with exquisite workmanship, to ensure the quality of products, making the electric bike chainring adapter durable and practical.SpecificationItem Type: Electric Bike Chainring AdapterMaterial: 6061T Aviation AluminumWeight: Approx. 100g / 3.5ozInside Diameter: Approx. 28mm / 1.1inPackage List1 xElectric Bike Chainring Adapter