175 gsm - The Polaris Crew: ideal for the discerning outdoorsman. Duckworth's proprietary Polaris fabric is designed to trap warm air in the miniature waffle knit construction, creating a lightweight yet incredibly warm layer, and 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 solo layer and let it breathe, on colder days, use it as a baselayer. The checklist: odor-free, itch-free, moisture wicking, durable, performance-driven, and versatile. By the way, this Montana-grown Merino Wool shirt looks real sharp for a night out.