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 Extreme Baselayer is our warmest yet, delivering extreme warmth in the extreme coldUA Scent Control Technology to keep you undetected in all pursuitsSoft, brushed grid interior traps air, managing your body's microclimate to keep you warm & comfortableMaterial wicks sweat & dries really fast4-way stretch material moves better in every direction¼ zip front allows you to dump excess heat quickly & efficiently
Polyester - 81%
Elastarell - 19%
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