The Wms Merino 250 Baselayer Crew Boxed by Smartwool is very soft, breathable, temperature-regulating and also nice and warm. The seams are flat and therefore do not chafe, which is further supported by the long raglan sleeves if you are wearing a backpack. The side seams are offset to the front for a feminine fit that accentuates the body. Wonderfully comfortable thermal underwear!