Mens nike flex rn 2017 running shoe adaptive fit zoned support top to bottom the mens nike flex rn 2017 running shoe is built to flex its one piece engineered mesh upper adaptive heel design and molded tri star outsole pattern work together for a smooth ride that moves with your stride dynamic flywire cables provide a one to one fit engineered mesh provides breathable support tri star outsole pattern enhances flexibility minimal heel design provides a more natural fit co