Design: An internal containment system gives you a more dynamic fit system that limits movement inside the shoe without feeling constricting In-Shoe Comfort: A top-loaded Zoom Air unit in the forefoot provides energy return and responsiveness Springy foam midsole has a responsive underfoot ride that adds a soft, comfortable sensation to help keep you moving and energized all game long Durability & Traction: Advanced traction in the heel enhances your on-court feel