Baselayer

UA Base 4.0 is built for extreme cold weather and lower activity. It uses a unique pattern that's designed to trap heat without adding bulk. Think long underwear, revamped for today's top athletes.

UA Base 4.0 is a men's baselayer built for extreme cold weather and lower activity. It uses a unique pattern that's designed to trap heat without adding bulk. Think long underwear, revamped for today's top athletes.

UA Base 4.0 is built for extreme cold weather and lower activity. It uses a unique pattern that's designed to trap heat without adding bulk. Think long underwear, revamped for today's top athletes.