These are a couple of HP Scorpions FS that we’ve converted to electric assist. One with the BionX DV 500w, and the other with a 750w Bafang Mid-Dirve. Both perform exceptionally well, smooth transition, and more than enough torque. The mid-drive beats out the BionX for power on throttle assist – only because of the battery which is a 52v. 13ah. Panasonic GA.