With supportive, bouncy cushioning built for a smooth run, the Nike InfinityRN 4 is an updated take on a familiar favorite. Our Nike ReactX foam gives you 13% more energy return compared with Nike React foam. (And Nike ReactX reduces its carbon footprint in a pair of midsoles by at least 43% compared to Nike React foam.*) We coupled the ReactX foam with Nike Running's best-fitting Flyknit yet, so every stride is supportive and breathable. *The carbon footprint of ReactX is based on cradle-to-gate assessment reviewed by PRe Sustainability B.V and Intertek China. Other midsole components such as airbags, plates or other foam formulations were not considered. More Benefits - Flyknit tongue is adjustable and plush. - Waffle outsole provides durable traction. - Foam collar is soft and supportive to the touch. - Increased rubber at the outsole gives traction and durability. Product Details - Shown: Sail/Vapor Green/Cargo Khaki/Crimson Tint - Style: HJ7666-133