LIGHTWEIGHT FLEXIBILITY, DYNAMIC CONTAINMENT. Designed for low-impact workouts and circuit training, the Nike Flex TR 9 pairs a breathable mesh and synthetic upper with a supportive platform designed for flexibility and traction. Mesh in the forefoot enhances breathability. Heel strap adds support and containment. Tri-star outsole pattern expands to disperse pressure. Foam midsole is durable enough to double as the outsole, dramatically reducing weight. Rubber in high-wear areas adds durability.Upper - Textile, Lining and Sock - Textile, Sole - Other Materials.