Gravely/Tory-Bilt/MTD/GardenWay Tiller - Tire Tube 4.80 / 4.00 - 8 (13573) Gravely/Tory-Bilt/MTD/GardenWay Tiller - Tire Tube 4.80 / 4.00 - 8 (13573) Fits Gravely walk behind tractors with 4.80 / 4.00 - 8 tires. Fits Troy-Bilt tillers with tire size 4.80-8 Gravely part number: 13573