Motor core replacement unit, complete with stator, rotor, gasket, magnets, hall sensors and board
The variants 68, 90, 100 & 120 mm differ from the attachment of the triangle. 100 & 120 mm have the same structure and work for both.
Original product from Bafang, for the BBSHD
You need to change the core if you have hall sensor error or your motor was overheating too much or shorted