Made with Polartec® Powerstretch®, this baselayer delivers warmth, durability, and exceptional 4-way stretch with a soft, cozy interior that moves easily with you. The body-hugging fit, seamless underarm gusset, and vent-ready collar keep you comfortable through both high-output and cold-weather conditions. Pair it with the Powerstretch® Bottom for an unmatched next-to-skin system.