The Zpacks Classic sleeping bag was the second highest scoring bag in our ultralight review in 2017 for the second test period in a row. It is a warm hoodless mummy that uses high-quality 900 fill power down in a box baffle design that really helps trap your body heat. With an enclosed footbox and ¾ length zipper, its design allows one to open it almost all the way up, making it highly versatile for such a warm bag. At only 20.3 ounces, it manages to retain a really low weight for how warm it is. We also loved that it comes with a great waterproof cuben fiber stuff sack. However, while it ranked highly in our cumulative scoring, it still has a few notable drawbacks, including a poor neck collar design and a tighter than average fit that held it back from being the best.
If thru-hikes like the Appalachian or Pacific Crest Trails are your goal, this is one of the best sleeping bags for paring down your base weight under 10 lbs, along with the Feathered Friends Flicker or the Katabatic Gear Palisade. The Zpacks model is the warmest and most lightweight mummy of products we reviewed. For a more affordable option, see our Best Buy Award winner, the Enlightened Equipment Revelation 20. It comes close in warmth to the Zpacks model, with plenty of versatility along with it.