"This baselayer top is my favorite for my active winter days. The midweight knit is warm enough to relax in without being so warm that I'm uncomfortable while hiking or skiing, and the zip cools me off quick." -Gearhead(R) Expert SammyOur Backcountry Cedars RWS Merino Midweight 1/4-Zip Baselayer Top delivers technical warmth and performance for our full repertoire of winter adventures. Responsible Wool Standard-certified merino wool lends its insulating, thermoregulating, and odor-resisting properties to keep us comfortable and fresh during active outings, and it's sourced from farms that consider the welfare of their animals and their land.