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 construction moves better in every direction. Material wicks sweat & dries really fast. Anti-odor technology prevents the growth of odor-causing microbes. Mesh panel on back neck with ARMOUR wordmark.