Keep on feeling cool, even when the activity heats up. Under Armour expands upon this tee???s moisture-wicking, quick-drying construction with mesh panels on the sleeves, sides, and back, designed to enhance ventilation and control perspiration.. . Body: 90% polyester/10% elastane. Back panel and insets: 100% polyester. HeatGear(R) fabric offers quick-drying and temperature-regulating properties to keep you cool. Crewneck with interior taping. Short sleeves. Mesh insets at shoulders, down the sides, and on the back improve ventilation. Four-way stretch construction gives you a full range of movement. Antimicrobial properties control odor-causing bacteria to help keep you fresh. Tagless neck. Next-to-skin fit is close but not restrictive. Imported.