If you are looking for a 4.10/3.50-4 tire and tube set with knobby tread for scooters, mini ATVs, and go-karts then we have just what you need. We took our 4.10/3.50 knobby pneumatic tire with its aggressive looking tread and 2 ply rating, and we now offer it bundled with its own inner tube. This is a great combination set, and the best part is the great price.