Reliable cushioning, good support and a smooth ride: the Nike InfinityRN 4 brings a cult model back to life in a new light. It is made with our brand new Nike ReactX foam, which provides 13% more energy return compared to React foam: you keep your energy for a dynamic stride. (What else? To take care of our planet, Nike ReactX reduces the carbon footprint of the midsole by at least 43% compared to Nike React foam.) We combined ReactX foam with Flyknit, the tightest-fitting Nike Running material yet. So you can run with confidence with the soft support and breathability of the upper. It's the kind of shoe that cushions every step.