Devold® Expedition – is proved on several polar expeditions, and is the only dual layer wool underwear with Aquaduct function. Expedition underwear is made from 95% pure new Aquaduct treated merino wool, providing warmth during demanding cold-weather activities. Even when the temperature drops below -50°C, the heat isolating and moisture absorbing qualities of wool let you feel warm and dry. The Aquaduct treatment improves moisture transport to the outside of the garment where evaporating. The polo model has extra long sleeves with thumb loops.