The Mizuno Wave Musha 4 racing flat provides the perfect blend of control and cushioning while offering an unsurpassed ride. AIR Mesh� upper provides the utmost in breathability and comfort. AP+ midsole offers increased rebound and a "bouncier" feeling, which extends the cushion durability, while maintaining the lightweight performance. Mizuno Wave� and SmoothRide� add cushioning and stability. X10� carbon rubber outsole allows for longer wear in high impact areas and supplements traction at the heel strike. Removable insole. Wt. 7.8 oz.