Versatile Base Layer Shirt: Perfect for everyday comfort and year-round layering performance, this running top features 100% merino wool rib fabric that’s soft, breathable, and odour-resistant. The stretchy slim fit provides easy-layering performance ideal for any active adventure. 100% Merino: Soft merino fibers that regulates body temperature in all weather conditions and resists odors. Inspired by Nature: Icebreaker harnesses the performance qualities of natural fibers to offer an alternative to clothing based on petrochemical synthetics. Renewable and Adaptable: Merino is an annually renewable fiber that naturally resists odours, keeps you cool when it’s hot and warm when it’s not, and lets your skin breathe for comfort.