Under Armour Women's HeatGear CoolSwitch Run Shirt 80% Nylon/20% Elastane Imported Fitted: Next-to-skin without the squeeze UA CoolSwitch uses an exclusive coating on the inside that pulls heat away from your skin, making you actually feel cool & able to perform longer Soft, incredibly lightweight construction delivers amazing breathability without sacrificing coverage UPF 30+ sun protection Signature Moisture Transport System wicks sweat to keep you dry & light