The Hub Motor for ERA 3 is different from any other models. 

Power system :

It fit Backfire ERA 3 and ERA 2, although different motor designs, wheels sleeves are different for ERA 2 and ERA 3.  It is working under the 10s power system from 36v to 42v input.  

Connector: 

9 pin

Options:

- Single Motor does not include wheel sleeve or hardware

- Motor Set include rear truck and two motors with wheel sleeves installed