The Nike VaporFly 4% Flyknit are neutral unisex running shoes especially designed for record breaking achievements. The flexible Flyknit upper of the shoes contours itself to the shape of the feet, creating a soft and snug feel. It offer excellent breathability and provides comfortable support. Added to the midfoot of the shoes is an arch band which encloses the feet when running.The Nike ZoomX Foam is responsive material that returns energy every step of the way. In addition the Carbon Fiber outsole helps to propel you forwards. The rubber outsole also offers excellent grip on street surfaces. Research has shown that athletes run 4% more efficient with the Nike Vaporfly 4% in comparison to the Zoom Streak 6, Nike's previous fastest marathon shoes. Therefore the Nike Vaporfly 4% Flyknit is the perfect shoe to break records with.