HOKA ONE ONE Women's W Odyssey 2 Running Shoe Synthetic Synthetic sole Lightweight Breathable Air Mesh Upper - Allows air to fully permeate the shoe, promoting a cooler, drier and altogether more pleasant environment. Structural No Sew SpeedFrame Overlays - Provide necessary stabilisation around the midfoot from medial to lateral with a seamless interior environment that reduces irritation and blistering. Padded Comfort Collar - Extensive padded paneling prevents the foot from rubbing against the collar, thereby reducing blisters. Oversize EVA midsole - 30% softer than traditional EVA foam that enables a smooth ride with increased propulsion. Early Stage Meta-Rocker Geometry - Specifically engineered with a low heel-toe differential and a sculpted outsole radius in the heel and toe, encourages a guided foot gait cycle; supports a runner's form and running mechanics.