275 gsm- If you're looking for a baselayer to stand up to the coldest winter days Mother Nature throws your way - and we've had customers wear Comet on expeditions in Antarctica and Alaska - then you've come to the right place. Duckworth's proprietary Comet fabric is natural-technical mash-up, combining a pure, 100% Montana-grown Merino Wool outer layer and a polyester inner layer. Why the combo? Polyester is hydrophobic, meaning it will wick sweat and moisture right off your skin and into the hydrophilic wool layer; wool chemically becomes even warmer when introduced to water and water vapor, thus explaining why the slim-fitted Comet Leggings will have your legs feeling dry and toasty even in the nastiest conditions. Soft to the touch, durable, anti-odor, moisture-wicking, quick-drying, durable, and versatile: your one-stop-shop baselayer legging.