More cushioned than the 3.0 and closer to the ground than the 5.0, the Nike Free 4.0 Men's Flyknit Running Shoe is designed to unleash your natural stride with a low-profile midsole and a lightweight, supportive Flyknit upper. Hexagonal flex grooves offer six points of flexibility to let your foot move naturally in every direction. Secondary cuts in the midsole enhance natural range of motion. The strong, lightweight Flyknit upper provides a contoured, supportive fit with stretchy polyester yarn. Flywire integrated with the laces delivers added support and an adaptive fit.