100% all natural superfine 18.5-micron Merino wool ensures comfort all day – no itch! Can be worn as a lightweight thermal base layer on its own. Quarter-zip design. Merino wool’s natural wicking and odor-resistant properties keep you dry and comfortable while active in cold weather. Through the process of wicking, Merino wool is the most breathable fabric and absorbs moisture better than any other fibers. Wicking refers to a fabric’s ability to pull moisture away from your body and keep you comfortable. Size Medium EUC