Our Backcountry Cedars Rws Merino Midweight 1/4-Zip Baselayer Top delivers technical warmth and performance for our full repertoire of winter adventures. 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.