Designed using Nike's signature Dri-FIT fabric, the Nike Pro Dri-Fit Skull Wrap 4.0 wicks away sweat to keep you dry and comfortable, and it was constructed with flat lock seams and a tapered design that provide a better, smoother fit over your head. Plus, it has an open top design that allows for extra ventilation. 84% Polyester, 16% Spandex.