13" Diameter, 6", Flat Free Residential Wheelbarrow Tire, 3.50/2.50 - 8", Also Known As A 4.00-6", 6" Hub, 5/8" Bearing, Solid, Lightweight Polyurethane Foam Tire Mounted On Steel Rim, Provides The Bounce & Feel Of Air Tires With The Benefit Of No Flats.