Merino wool is already an incredible material, and I'm so stoked that we were able to achieve Responsible Wool Standard certification. -Gearhead(R) Expert JessieThere's nothing like our Backcountry Cedars RWS Merino Lightweight Baselayer Bottom to deliver backcountry comfort, whether we're strutting the skin track, hiking snowy hills, or exploring our city in the winter. RWS-certified merino wool provides excellent moisture management and temperature regulation while delivering next-to-skin softness and resisting odor buildup. With a boost of durability from nylon and a comfortable, stretchy design, it's easy to stay active throughout the season.