The king of the cushioning jungle. Slip these running shoes on and treat your feet to the revolutionary cushioning of boost™. boost™ feels amazing underfoot, never packs out, and returns energy to your run with every step. The light, durable STRETCHWEB outsole is designed to work with boost™ to provide a fluid, heel-to-toe transition. And metallic yarn woven throughout the knit and synthetic upper gives it a subtle, shimmering appearance.