On those cold days outdoors its important to wear a breathable base layer that keeps you warm and balances temperature. Thats why Mammut developed the Trift line that features a Merino wool/polyamide blend. The wool content insulates and inhibits odors, the synthetic fibers make the long sleeve top durable and quick-drying. Seamless construction allows a body zone-specific arrangement of different material structures for optimal regulation of your body temperature. The half-length zipper allows extra ventilation. MAMMUT obtains its Merino wool from suppliers who care about animal welfare and are against mulesing.