Product details:

The ingenious design dumps excess heat when you are on the move, but holds it in during downtime. Polartec Alpha Active Insulation is layered between a polyester mesh lining and a highly breathable nylon shell making Outdoor Researche's UberLayer a backcountry chameleon. It provides the warmth of a synthetic puffy one moment and the breathability and quick-dry performance of a fleece the next, all without forcing you to add, remove or adjust your layers.