https://www.etong-ev.com/products/4-wheel-electric-mobility-scooter/ 4 WHEEL ELECTRIC MOBILITY SCOOTER With four wheel design, this four wheel drive mobility scooter 's center of gravity is stable and turning will not roll over. When in turning, the mobility scooter electric 4 wheel's whole plane rotates to ensure smoothness and safety. The four-wheel design breaks the rule of triangle stability, which is more safe than 3 wheel electric mobility scooter.