What goes up must come down, and you live to do both even when the winter winds are howling. Whether you're heading out for backcountry ski tours, gnarly ice-climbing and mountaineering ascents, or a heart-pumping powder day at the resort, you don't flee from the mountains when they get a bit cold. That's why the Patagonia Nano-Air Insulated Hooded Jacket will be a mainstay of your winter wardrobe as you stay active in the ice and snow. The Nano-Air was designed by Patagonia as a breathable insulating layer to keep you warm and comfortable during high-output missions in the cold, so you can avoid constantly changing your layers when you're working hard in the winter. The Nano-Air gets its active performance from the innovative insulation and air-permeable fabric construction. While the soft yet strong fabric lets just the right amount of air in and out, the FullRange insulation moves with you comfortably and regulates your temperature so you never feel too clammy or too cold as you move. And while Patagonia has developed lighter and more hybrid versions of the Nano-Air, the original hoodie remains the warmest and most versatile for stand-alone and layerable wearing on frigid days in the mountains and around town. A DWR (Durable Water Repellent) gives you light weather protection from drizzly rain and moderate snowfall, and the snug-fitting elastic trim hood keeps your ears and face protected from cold winds, even under a helmet.