Improve Compatibility with For Bafang MidMotor Spider ChainRing Adapter
For bafang M500/G520, M510/G522, for M600/G521M620/G510, M420/G332, M615/M820. easy to use and install,M620 G520 needs to add a washer good compatibility. Specifications: BCD104mm-can match chainrings with different numbers of teeth.