Note: this is a unisex-sized shoe. Men's sizes are shown — women should order 1.5 sizes below their standard running shoe size. For example: for a women's size 9.5 shoe, order a size 8. FLEXFILM - A strong, lightweight material is melded to the upper, which allows for fewer layers in the shoe. The result is a seamless, flexible feel. ISOFIT - Revolutionary fit system that morphs to the foot for a custom feel.