This versatile hoodie has been tested in the Alps and can be worn as a middle layer and independently, and has kept climbers and field travelers warm for years. The latest generation of Atom's Coreft ? Compact insulation is designed to handle a variety of conditions and output levels, remains warm even in humid conditions, and has a fluffy degree that can withstand years of packaging and unpacking. The waterproof Tyono? 20 fabric is breathable and durable, elastic side panels enhance fit and freedom, and the insulated StormHood? adds warmth.