The newInfinity Wheel Packhas the air tire feel without the air tire maintenance. Turn your Stroller into a light weight All Terrain Stroller producing a smoother ride and better suspension and no need to keep pumping up with air! Wheels come in storage bag with a convenient carry strap, to store them or the lightweight EVA Tires when swapped with Infinity wheels They can be left on your stroller for everyday use or swapped over when the situation arises. The Valco baby Infinity Wheels Pack comes in two diferent models, one suitable for the Trend Series, including the Trend Ultra, Trend Duo and Trend 4.