We built our Backcountry Cedars Rws Merino Midweight Crew Baselayer Top for cold-weather play. The Wool Standard-certified merino wool fibers are sourced from animal- and friendly farms, and they deliver the anti-odor, temperature-regulating technology we love. With nylon enhancing durability and spandex for stretch, this midweight material is sure to provide active comfort for winter hikes, skintrack ascents, and terrain park laps.