The Patagonia Nano-Air® Jacket was made to be worn for the entirety of your aerobic, start-stop alpine missions. No pause to swap layers, this is designed so you’re never slowed down with warm, stretchy and breathable FullRange® insulation that dumps excess heat when you’re working hard and keeps you warm when you’re not. Don’t you love technical fibers? Stretchy, breathable, and water-resistant this is a layering piece that packs down into its own pocket and can be clipped to the outside of a pack, ready to be deployed at a moment’s notice. Designed for movement and next-to-skin comfort, whether you’re wearing a tee or a baselayer, this has the stretch, and the tailoring, suited to climbing, with harness compatibility, and the heat management you need for sports like cross country skiing, winter running, and cold weather biking. Tailor made for men looking for versatility in their sportswear it’s a piece that layers, packs, and works well on its own.