BK10S Foldable Electric Bike 20"x4 Fat Tires E-Bike 5OOW 48V/13Ah 90km Range. Koolux BK10s. Powerful and Stable 5OOW Motor. Motor Power: 5OOW. 48V 13Ah Battery for Worry-Free Travel. Features three riding modes: pedal assist, pure electric, and classic pedal.