Built for smooth miles, the Nike InfinityRN 4 Running Shoe pairs plush cushioning with secure support. Its all-new Nike ReactX foam delivers 13% more energy return than Nike React to keep strides feeling fresh, bouncy, and consistent. Breathable, best-fitting Flyknit upper hugs the midfoot for lockdown while allowing airflow. An intuitive design promotes stable transitions so you can go faster and farther. ReactX also reduces the midsoles’ carbon footprint by at least 43% per pair compared to Nike React. Features Outsole Traction: Waffle outsole provides durable traction for confident grip on varied surfaces. Flyknit Tongue: Flyknit tongue is adjustable and plush for personalized comfort throughout your run. Foam Collar: Foam collar is soft and supportive to the touch, reducing irritation during movement. Outsole Durability: Increased rubber at the outsole adds traction and durability for long-lasting wear.