The Under ArmourA(R) 4.0 Quarter-zip Extreme Base Layer is Under Armour's warmest layer yet. Built for extremely cold temperatures or lower activity levels. The material wicks sweat and dries really fast, offers odor control, and its brushed grid interior traps air, managing your body's microclimate. 93/7 polyester/elastane Quarter-zip neck allows you to vent heat as needed Under Armour's warmest layer Odor-control technology keeps you fresher, longer Brushed grid interior traps air next to your body, keeping you warmer Moisture wicking and fast drying 4-way stretch material moves with you Fitted, streamlined fit Order today!