The Ultra 3 is a more modern take on the Ultra 2 with its bouncier and softerSuperFOAMance midsolewhich is made of hi-tech and ultralight nitrogen infused material that offers extreme cushioning and energy return. This new foam is a modern, supercritical foam that is lighter, more responsive, more comfortable and more propulsive than a traditional EVA foam. Compared to other foams, SuperFOAMance is more durable and does not rip as easily.