React technology from Nike is a new midsole cushioning system that delivers unbelievable response and comfort while maintaining integrity so you can keep pushing mile after mile. React foam gives you a soft, springy sensation that helps power your run. The Epic React Flyknit is also constructed with a Flyknit upper that forms to the shape of your foot, giving you adaptive support and comfort. Its foam outsole retains its shape and adds lightness to the shoe while rubber sections at the toe and heel provide traction and durability. Flyknit forms to the shape and movements of your foot. Bootie-style construction with a seamless tongue limits distractions and pressure. Heel shelf stabilizes the back of your foot. Nike React foam cushioning is responsive yet lightweight and durable yet soft. Foam outsole resists compression for hundreds of miles. Rubber sections on the toe and heel for grip and durability.