Features： 1、Applicable Model: 104 BCD electric bike chainring and adapter is compatible for Bafang electric bike mid drive motor BBS01 BBS0. 2、Aluminum Alloy Material: The material is aluminum alloy, the hardness is much higher than the original steel sprocket, sturdy and durable. 3、Aluminum Alloy CNC Cutting: Using aluminum alloy CNC cutting to ensure product use accuracy. Exquisite workmanship, beautiful appearance. 4、Applicable Speed: The 104 BCD electric bike chainring and adapter fits 7, 8, 9, 10, 11 speeds, effectively improve the performance of electric bike. 5、Closely Fitting: Closely fit the original machine hole position with accurate shape and size design, hand feelings are still comfortable. Specification： Item Type: 104 BCD Electric Bike Chainring and Adapter Material: Aluminum Alloy BCD: 104MM Fits: 7, 8, 9, 10, 11 Speeds Package List： 1 x 104BCD Chain Ring Conversion Kit