For The Benefit of Mankind: The World's Most Comfortable Underwear UA's signature Moisture Transport System and temperature regulation gave athlete's something they'd never had before?a performance alternative to all the other underwear in their drawer. Forget your old underwear that bunches up, wears out, or loses its shape; UA's O Series underwear stretches, recovers, and fits exactly how you want it to. Anti-Odor Technology prevents the growth of odor causing microbes. 3-inch inseam. 95% Polyester / 5% Elastane.