Nike React Infinity Run Flyknit 4 - Women'sWith supportive cushioning built for a smooth run, the InfinityRN 4 is a brand new take on a familiar favorite. Its made with our all new Nike ReactX foam, which gives you 13% more energy return compared to Nike React foam, to help you stay fresh and bouncy. (Whats more? Nike ReactX reduces the carbon footprint of the midsole by at least 43% compared to Nike React foam, so it helps support the planet too.) We coupled the ReactX foam with Nike