Perfect for outdoor winter workers, or extreme cold skiing, the men’s EXTREME TOP is like your own little furnace! In fact, the technology behind this fabric uses your own body heat to keep you cozy warm. Breathable, super soft and insulating with great wicking capability, this is modern day underwear that make sense. Give up your baggy t-shirts, cotton is NOT a good insulator by the way, and pull on a Winter Woolies EXTREME TOP for incomparable comfort. For any winter sport and for those cold weather work projects outdoors, button up and team up in an EXTREME top and pants set. Believe it…..you CAN…… Kill The Chill!