Under Armour Men's HeatGear Armour Printed Long Sleeve Compression Shirt 84% Polyester, 16% Elastane Imported HeatGear fabric, with all the benefits of UA Compression, comfortable enough to be worn all day Stretch-mesh underarm panels deliver strategic ventilation UPF 30+ protects your skin from the sun's harmful rays 4-way stretch fabrication allows greater mobility in any direction Moisture Transport System wicks sweat & dries fast