NIKE Free 5.0+ Mens Running Shoes 579959-700 Synthetic The flex groove outsole-made up of deep cuts along the length and width of the midsole-enhances natural range of motion, encourages a smooth, efficient stride and helps maintain stability A low-profile midsole delivers a natural barefoot-like feel. It features the highest offset offered by Nike Free running shoes, with an 8mm difference between heel and forefoot height for greater cushioning while still promoting a natural stride. Plus, the Phylite material in the midsole is tough enough to double as an outsole, dramatically reducing the shoe's overall weight The Nike Free 5.0+ is the most supportive of the Nike Free family thanks to ultra-light Flywire technology. This updated version of Flywire consists of soft yet durable cables that wrap the midfoot and arch from underneath the foot for a glove-like, supportive fit that adapts to your stride