With a soft, cushioned, and energetic midsole made from nitrogen infused ENERZY NXT the Mizuno Wave Sky 9 uses FOAM WAVE technology to create increased stability without sacrificing the softness. They have also made the outsole wider for improved stability and added in even more foam for improved plush softness. A smooth stretch woven upper envelops your feet in a breathable, comfort fabric to enhance the luxurious feeling of softness on your run.