NIKE Lady Dual Fusion Running Shoes Breathable mesh upper - For breathability and a comfortable fit Dual Density Phylon Foam - With soft foam in the center and firm foam at the perimeter for plush, supportive cushioning Flex Grooves - At the midsole and outsole for enhanced flexibility and natural range of motion Inner Sleeve - For a soft, comfortable fit. Waffle lugs - Located at the outsole for impact absorption and better traction.