The Nike Free Run 2018 Shoe has been updated to deliver an even more adaptive fit than before. Stretch material in the upper moves with your foot, while the tri-star outsole pattern adjusts to your every step for a ride that delivers support and flexibility. Circular-knit upper is made with spandex for natural movement. Dynamic heel fit system gives you support from heel to ankle. Flywire cables integrate with laces for an adaptive, supportive fit. Texture has been added under the toe and heel to enhance traction in these high-abrasion zones.