All-terrain mobility scooters include knobby tires, robust motors, and boosted ground clearance to deal with gravel paths

https://www.4shared.com/office/it5ByLUPge/pdf-95287-87477.html

All-terrain mobility scooters add knobby tires, robust motors, and enhanced ground clearance to take on gravel courses, yard, and mild off-road surface areas.