NIKE Boy's Flex Experience RN 7 (PSV) Running Shoes Synthetic Fuel their passion to run with the Nike Kids Flex Experience Run 7 sneaker. Lightweight mesh upper with no-sew synthetic overlays is designed for a streamlined, sock-like fit. Injected foam midsole doubles as an outsole, supplying lightweight comfort. Lightly padded tongue and collar. Breathable fabric lining.