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

https://www.4shared.com/office/oK7KL-c8fa/pdf-12321-58562.html

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