Marathon 00003 Flat Free Wheelbarrow Tire on Wheel, 6" x 13"This tire is perfect for residential 4 and 6 cubic foot wheelbarrows. It is often referred to as a 4. 00 6. Lightweight polyurethane foam tire mounted on steel rim. Provides the bounce & feel of air tires with the benefit of no flats. Tire type: flat free Tire size: 3. 50 2. 50 8" Tire diameter: 13. 3" Tire width: 3. 2" Rim diameter: 8" Load capacity: 300 lbs Also known as a 4. 00 6" 6" hub 5 8" bearing, solid Lightweight polyurethane foam tire