Under Armour Men's Rival Polo 100% polyester Textured fabric is soft, light & breathable Material wicks sweat & dries really fast Anti-odor technology prevents the growth of odor-causing microbes Mesh insets on sleeves cuffs for added breathability HeatGear® is engineered with a microfiber blend fabric featuring the signature Moisture Transport System and reliable compression. It's designed to fit tight to your skin, under your outerwear.