Keep A Cool Head The heat never gets to you when you put on the Under Armour Iso-Chill ArmourVent™ Adjustable Cap. The ArmourVent™ technology provides great breathability while the sweat-wicking construction ensures your head stays dry. Give your headgear a cool update with this cap. Under Armour Iso-Chill ArmourVent™ Adjustable Cap Features: 54% Nylon/31% Polyester/15% Elastane Fabric used is light, stretchy, durable, and fast drying ArmourVent™ Technology Sweat-wicking material Iso-Chill sweatband and front panel lining disperse body heat Adjustable back closure