This one looks the same on the outside but on the inside its completely different, it has a two speed automatic transmission. When the Spinweight is moving in one direction, pedalling forward or clockwise it will engage one drive ratio. When it is going in the other direction, pedalling backward or counterclockwise it will engage another higher drive ratio. This makes it easy enough for a small child on the low end of the powerband and on the high end once the rotor starts spinning a few hundred miles per hour its strong enough to take any athlete to Vo2 max in 90 seconds.