The Nike Free Run Flyknit uses a one-piece Flyknit upper to conform to the needs of your foot. The Flyknit thread is tightly woven in areas that require more support, while a looser weave allows cooling airflow in the forefoot. Flywire cables at the midfoot provide adjustable support and lockdown through the laces. Low-profile midsole and rounded heel create a smoother footstrike and running gait. New tri-star outsole pattern expands at impact and contracts at toe-off, following the natural movement of the foot throughout your running stride.