Design: Evolved Flyknit upper places zones of breathability where your foot heats up most Upper is strong and durable, helping keep your foot secure with every mile Heel clip is smaller than the previous iteration and is placed in a more precise location Wider midsole adds stability Reflective details add visibility In-Shoe Comfort: Taller foam stacks than the previous version raise the bar on cushioning and comfort, in a more sleek-looking design ZoomX cushioning, shaped like a rocker, gives you ultimate cushioning at ground contact and a soft underfoot feel ZoomX foam is ultra-responsive and lightweight, giving you bounce and a snappy response with every step