The versatile LIFA Merino crew adapts to any type of cold weather. We combined a 100% merino wool layer with our proven LIFA Stay Warm Technology in a fitted 2-layer construction. LIFA Merino Midweight Crew Base Layer delivers all the breathable warmth of merino wool fibers, plus the unique moisture management properties of LIFA fibers. Features: 2-layer construction 100% Merino wool exterior Flat lock seams for ideal comfort and durability Non-itch fabric Composition Shell: 57% Merino Wool, 43% Polypropylene. Machine wash in luke warm water - 40°C very gentle cycle,Do not bleach,Do not tumble dry,Do not iron,Do not dry clean Use wool detergent,Do not use fabric softener,Wash inside out,Do not wring.