P001: Power Pack fits wheelchair width of 36-51cm (14-20"). It lifts out of use to enable normal wheelchair function. Removable battery pack for remote charging.It has security key switch and variable speed setting with reverse. It is simple to operate hand control lever. Dismantles effortlessly for easy transportation and storage. Twin drive wheels for greater traction at the back. It is suitable for users up to 136 kg (21 stone).