Zappos.com is proud to offer the Mizuno Running - Wave Ascend (Lapis/Sun/Navy) - Women's: Designed for the runner with medium but flexible arches who demands excellent support and cushioning to tackle the extremes of off-road running. Composite Fan Wave technology provides a great blend of support and cushioning for the runner looking for a low-profile option that can handle the rigors of trail running. 23/11mm (heel to forefoot ratio). The combination of rubber(lateral) and Pebax(medial) creates a wave capable of preventing overpronation in the heel to midfoot phase of the gait cycle. Outsole: X-10 rubber in the heel for durability; 6mm outsole lugs provide traction; Shoe weighs 10.2oz.