Design: Updated two-color engineered mesh upper provides exceptional comfort and breathability A rocker shape is designed to give the feeling of being propelled forward with each step and provides an efficient toe-off without taking away from your natural stride Altra's signature FootShape gives you plenty of room to help your toes move freely, with a secure midfoot Zero to low drop is built to place your fit in a natural position In-Shoe Comfort: Compression-molded EVA foam is lightweight, responsive midsole foam that encourages efficiency and an effortless feel GuideRail(TM) technology provides neutral support for a stable ride Durability & Traction: Rubber outsole provides grip and durability Additional Details: Best For: Road running, walking Heel-to-Toe Drop: 4mm Stack Height: 26mm/30mm Weight: 9.6 oz / 272 g