The DoubleWool is made from a superb mixture of materials: WoolNet Original in towards the body and WarmWool as the next layer. By combining these fabrics, Aclima made a product with optimal wicking properties, at the same time ensuring excellent insulation by allowing air to flow between the layers. They claim that this is the warmest woolen underwear on the market. Extra exposed hardwearing areas of the body such as knees, shoulders and elbows have been protected with two layers of WarmWool. Aclima DoubleWool is made for those who like to stay outdoors, even in extreme cold weather.