NIKE Lady Free TR FIT 2 Cross Training Shoes Synthetic No-sew construction - at upper to minimize seams for less irritation, meaning you can concentrate on your workout. Air mesh upper - for maximum breathability, keeping your feet cool and dry. Phylite midsole With engineered longitudinal and latitudinal sipes for a much better and effective running experience Deep flex grooves - Located along the outsole for greater flexibility, smoother and efficient ride. Flexible neoprene heel counter - that supports the foot and keeps it in place.