Teeth: 34T ,36T ,38T,40T options. Used to replace electric bike part，forM500 M510 for M600 M620 G510 G521 series motors. easy to use and install,M620 G520 needs to add a washer good compatibility. The real color of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness.
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