The all new Free Run+ 3 from Nike is the most recent update to the Free Run collection. Nike recognized early the benefits of a "less is more" approach, and continue to be a leader in this area with the new Free series. Runners who have used previous versions of the Free will recognize the deep flex grooves cut into the outsole; the Free Run + 3 has added transtarsal flex grooves which are midsole cuts that run diagonally under the midfoot area to increase the flexibility of the shoe. Additional updates include a new upper material that is ultra thin and seamless, yet breathable. The Free Run+ 3 also includes the supportive inner sleeve (familiar to fans of the new Zoom Elite, Lunarglide 3, and LunarEclipse 2) that wraps around the arch to provide a dynamic fit. Specifications:Upper- Nano-ply engineered suede composite that is laser perforated in strategic zonal areas of upper for adaptive fit. Seamless innersleeve tongue construction. Midsole- Off-set 17/13mm heel to forefoot drop. Transtarsal hot knife sipes for natural motion flexibility. IU midsole foam for lightweight durability. Outsole- BRS 1000 carbon rubber and environmentally preferred rubber inserts enhance durability at high-wear zones.