Mizuno Women's Wave Rider 11 Running Shoe Midsole Material: AP Midsole--The AP midsole provides lightweight, responsive cushioning. Cushioning Technology: Mizuno Wave--Disperses impact forces uniformly over the length and width of the midsole, providing unrivaled cushioning. Heel Technology: VS-1--VS-1 absorbs shock and enhances cushioning properties by resisting compression-set, thus extending the cushioning life of the shoe. Outsole: X-10--Durable carbon rubber that allows for longer wear in high impact areas and supplements traction at heel strike. Lacing System: Traditional Lacing System--Traditional lacing system provides a tighter fit for more centralized support.