Our LIFA® Merino Midweight collection is perfect for any type of activity in cold weather.We combined a 100% merino wool layer with our proven LIFA® Stay Warm tech in a 2-layer construction on this ½ zip.LIFA® Merino Midweight Base Layer delivers all the breathable warmth of merino wool fibers, plus the unique moisture management properties of LIFA® fibers.Composition:Shell:57% Merino Wool, 43% Polypropylene. Compare prices from: Helly Hansen in Men's Underwear