The base layer is the core component of your outdoor apparel, and the foundation of the layering system. For winter sports and outdoor activities in colder weather, men’s base layers should be lightweight, moisture wicking and breathable in order to provide the best possible level of comfort and versatility. Men’s long underwear and thermal underwear is designed to let your skin breathe, prevent overheating during periods of heavy activity, and dry quickly during rest periods to prevent chills. Men’s base layers and long johns come in an array of performance fabrics, including polyester, merino wool and silk. Unlike cotton, these materials make excellent thermal underwear because they are light, breathable and wick sweat away from the skin for fast evaporation. Upgrade your comfort level on your next adventure and outfit yourself with men’s base layers and long underwear from Terramar, Wickers and Icebreaker.