Du-Bro Large Scale Treaded Inflatable Wheel 4" Part No: 400TV. Du-Bro treaded wheels are narrower in width to fit inside wheel pants and retracts easier. Comes with 3/16" (5 mm) axle diameter and can be drilled out to 1/4 (6 mm) if desired. Comes complete with our positive seal air valves and inflator adapter. Diameter: 4.00" (102 mm), Axle Diameter: 3/16" (5 mm), Weight: 138grams/wheel, Width:1.175" (29.8 mm)