Devolds Expedition base layers have won numerous base layer tests, and many people swear by them. This Arctic Pro special edition is even warmer, and comes with body-mapped panels! Like the standard model, the construction is double-layered, but in Arctic Pro the fabric weight varies by area, and the outer layer is 90% Aquaduct-treated merino wool, which dries faster than regular merino wool. The remaining 10% of the outer layer is silk. The Expedition Arctic Pro is the right choice for winter trekking, outdoor activities, and even ice fishing. Merino wool feels pleasant against the skin and regulates temperature fluctuations: many hikers simplydrytheir merino base layers at camp by wearing them under other clothessituations where a synthetic base layer would quickly feel far too cold. - Regular fit - Back of thighs, shins, and calves: 235 g/m² fabric, fiber thickness 18.7 microns (inner fabric) and 20.5 microns (outer fabric) - Front thighs and seat area: 310 g/m² fabric, fib