NIKE Free 5.0+ Womens Running Shoes 580591-500 mesh Rubber sole Lightweight meshes with dynamic Flywire technology and adaptive inner sleeve to create a snug yet flexible upper that moves with the natural motion of the foot Flex grooves within the Phylon midsole allow the foot to move naturally in multiple directions Phylon from the midsole combines with strategically placed lugs of rubber provide a durable and minimal lightweight feel