All-terrain mobility scooters add knobby tires, robust motors, and improved ground clearance to take on gravel courses

https://www.4shared.com/office/L4lABYG6fa/pdf-33766-13142.html

All-terrain mobility scooters include knobby tires, robust motors, and improved ground clearance to deal with gravel courses, turf, and moderate off-road surfaces.