Nike Flex Trainer 9 | Women’s Size 7 Cool Grey Athletic Training Running Shoes. Previously owned, in great condition. About this item: LIGHTWEIGHT FLEXIBILITY: Built for low-impact workouts and circuit training, these women's shoes are designed for flexibility and traction. DYNAMIC CONTAINMENT: Synthetic upper and heel strap of the Nike shoe adds support and containment. DURABLE DESIGN: Foam midsole is durable enough to double as the outsole, dramatically reducing weight. Rubber in high-wear areas adds durability. BREATHABLE COMFORT: Mesh in the forefoot of these women's sneakers enhances breathability. Tri-star outsole pattern expands to disperse pressure. Description: 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.