Under Armour HeatGear ArmourVent Apollo SS Tee - Men's Fabric is light, extremely soft and wicks sweat fast to keep you cooler ArmourVent mesh panels deliver true breathability in a light, stretchy, durable, fast-drying fabric 4-way stretch fabrication allows greater mobility in any direction Anti-odor technology prevents the growth of odor causing microbes Reflective logos deliver greater visibility on low-light runs