A few days in Utah's backcountry will give you two things some of the best powder on the planet and a new appreciation for the word cold. The Columbia Women's Base Layer Heavyweight 12 Zip Top protects you from the cold so you can focus on skiing and not on the temperature. This heavyweight layer is constructed from Omni Heat, which is a thermal reflective waffle weave textile that helps to retain body heat next to the skin. At the same time, this material also allows moisture to escape, resulting in warm and dry skin. For added ventilation, though, Columbia placed inserts of Omni Wick at the sides and underarms in order to help dissipate additional moisture. The base layer features a 12 zip front and flatlock seams for comfort under your shell.