The Nike Vaporfly 4% Flyknit, as the name suggests, incorporates a new one-piece knit upper that seamlessly hugs the foot. The change from a lightweight mesh used on the previous version reduces irritation and improves breathabilty, too.
The new Flyknit model uses a one-piece bootie-like construction that fits exceptionally snug around your foot. It’s definitely a racing fit, with a tapered design to contour to your midfoot and opening just enough in the front to accommodate your forefoot.
The design is a lot like what we’ve seen on the Epic React Flyknit, but the knit used here is even less stretchy, which runners will appreciate as it bolsters support. The upper lacks any other typical reinforcements like overlays and a heel counter, but does have thinly padded patches and sueded materials inside to secure the foot to the soft platform.