These aren’t your grandpa's long underwear. The patented negative grid traps ridiculous warmth without adding excess weight. UA Base™ 3.0 is heavyweight protection in a lightweight layer. It provides superior warmth for times when you know you'll need it.
UA Base™ 3.0 is built to fight the bitter cold without weighing you down
Soft, brushed negative grid interior traps hot air, providing superior warmth
4-Way Stretch fabrication allows greater mobility and maintains shape