Duckworth's proprietary Polaris fabric is designed to trap warm air in the miniature waffle knit construction, creating a lightweight yet incredibly warm layer. The super soft waffle construction is meant to be worn directly on the skin, making the Polaris Crew the ideal crossover piece. On hotter days, wear it as a stylish and comfortable solo layer, or on colder days use it as a warm and cozy baselayer. Odor-free, itch-free, moisture wicking, performance-driven, and versatile, this Montana-grown Merino Wool shirt looks just as good on a night out as it does on a mountain's summit. Composition: 80% Montana Merino Wool, 20% American Polyester Weight: 175 gsm