The ultimate baselayer in colder conditions Devold Expedition is an underwear garment designed with dual layers for extreme weather conditions. Proven on several polar expeditions. The inner layer is made of 100 % Merino wool, while the outer layer is 90 % Aquaduct treated Merino wool, combined with 10 % polyamide to improve durability. Devold Expedition insulates extremely well and has a unique ability to transport moisture. The Aquaduct Merino wool is specifically designed to move moisture away from the skin side of the fabric to the outer surface where it evaporates.