The Cloud Nine Half-Zip Top is the ideal piece for all day warmth and comfort while being out in the elements. This versatile piece features an ultra-soft, midweight fabric utilizing Terramars ClimaSense Thermoregulation Technology that automatically adjusts to your body temperature. It does this by trapping air to maintain warmth when your body starts to cool down. When your aerobic activity increases and your skin temperature rises, the fabric allows moisture vapor to escape to maintain comfort. Whether skiing, mountaineering, fat biking, snowshoeing or winter running, Cloud Nine is functional performance at its best! The Womens Cloud Nine 2.0 Half-Zip goes perfectly with the Womens Cloud Nine 2.0 Pant and other pieces from the Cloud Nine collection.