Built to be super-lightweight, to dump heat to help keep you cool, and to wick sweat to help keep you dry. UA Free Fit: pre-curved visor & unstructured front conforms to your head for a sleek, low profile fit Durable, stretch woven fabric provides a comfortable fit & feel Mesh panels & backing for strategic ventilation Iso-Chill sweatband helps disperse body heat, making it feel cool to the touch Adjustable hook & loop closure Reflective details BODY: 100% Nylon MESH: 100% Polyester LINING: 91% Nylon/9% Elastane Imported