Brooks Women's Ariel Mesh and synthetic Rubber sole Full Length BioMoGo provides a more cushy first feel that lasts and is enviornmentally friendly Rearfoot and Forefoot Hydroflow enhance midsole cushioning Extended Progressive Diagonal Rollbar stabilizes the foot from heel-strike to toe off by progressively guiding the foot into a more biomechannically efficient position DRB Accel provides torsional rigidity to midfoot, enhancing support Full-length S-257 Cushsole gives the runner even more cushion with each stride