The ultra-light electric motor is unique in terms of aesthetics and function. Built invisibly into the seatpost, the 200 watt motor works directly on the crank. Since the motor comes as a retrofit kit you can install it in nearly every kind of bicycle. You barely even notice the additional drive unit and battery weight of just 1.8 kg . Thus the world's lightest mountainbike - under 10 kg - was born. The bike works as normal when the motor is switched off. Freewheel assembly means there is no resistance and you can continue to use the bike as sports equipment.