Our award-winning, best-selling three-season sleeping bag. Featuring our state-of-the-art ExtremeLite™ shell fabric, an efficient mummy shape and 850+ fill power ethically sourced goose down, the UltraLite is the perfect companion for any, or all, of your backcountry adventures. Whether it’s the John Muir Trail or a weekend getaway, the UltraLite has all the features you need to stay warm on the trail, without sacrificing weight, durability or volume.