NIKE Free TR Fit 3 Women Running Shoes 555158-402 mesh Mono-mesh combined with weblite TPU film overlays throughout the midfoot and forefoot to provide lightweight support, breathability Full-length Phylon midsole provides soft, lightweight cushioning, combined with new ramp Air-Sole unit for enhanced structural support and durability Environmentally preferred rubber modified Waffle outsole provides durable traction. Deep flex grooves improve flexibility