Despite providing best-in-class warmth, this bag weighs in at an impressive 1.86 pounds for a size long. The Western Mountaineering Cypress Sleeping Bag is a very well-constructed bag. The Warmth: The Western Mountaineering UltraLite is a 20°F / -6.67°C bag. If you take care of it, you won't have to worry about replacing it for a very long time (or maybe ever). All trademarks property of their respective owners You help support OutdoorGearLab's product testing and reviews by purchasing from our retail partners. According to Western Mountaineering, the T Comfort rating of the UltraLite is 25°F / -4°C (the lowest temperature a female can remain comfortably warm at), the T Limit rating is 14°F / -10°C (the lowest temperature a male can remain comfortably warm at), and the T Extreme rating is -21°F / -29°C (the temperature at which you could – possibly – be kept alive by the bag without literally freezing to death). You basically can't go wrong. Under the foot boxes I placed two identical trays with 0.5″ of water to simulate puddles.

Hunting season was long gone by the time the KUIU Super Down hit my doorstep, so I’d have to do the test in my backyard in winter conditions.

This was done easily enough by opening the bag, and shaking the insulation into the topside baffles. Keep in mind, this is not a controlled scientific test, but it does show the modern designs of these bags can get you through a soaking without losing the insulating properties of the bags. They list the WMB EN tested T Limit at 11°, but conservatively rate the bag at 15°. The graphics have started to wear off and it has some down bleed, but it is holding up well. I have a, ExtremeLite shell fabric encases insulation without unnecessary weight, 16 oz / 454 g of ultra-premium, 850-fill down insulation, Interlocking draft tubes and a down-filled collar prevent drafts, Slightly narrower shoulder girth to eliminate pockets of dead air for improved warmth retention, Comes with a stuff sack and a storage sack. Thank you for your support! It is made from material that makes it seem indestructible; so, you never have to worry about the quality and durability of the sleeping bag.

These bags are expensive but worth the extra money for the performance they provide and the f… It's something you won't have to worry about upgrading or replacing until you decide to start winter backpacking. These dimensions, however, are similar to most of the other standard mummy bags we tried.

The last hour, I felt a little chill set in, again on my thighs. The Western Mountaineering UltraLite is an 850-fill down, 20°F / -6.67°C, three-season, mummy sleeping bag weighing 29 oz / 936 g. Western Mountaineering has a reputation for being conservative in their bag ratings (meaning that you can trust a 20°F / -6.67°C bag to be a 20°F / -6.67°C bag), and the UltraLite is no exception to this trend. Beginner Backpackers: Honestly, the only reason I wouldn't suggest that you get an UltraLite as a beginner backpacker is the price. When word got out that I’d be testing this bag, many of our Rokslide members asked if I could test the KUIU Super Down against the Western Mountaineering Badger MF (WMB), another top-tier bag. I learned from one Rokslide member, sndmn11, that this design allows the user to shift the down from the underside of the bag to the topside, adding insulation to where and when it’s needed. This field is for validation purposes and should be left unchanged. A third-party compression sack can get it down to 8.7 liters in volume. *As of press time, KUIU has pulled their 15° bag from their website, only the 30° and the 0° are shown. I have long been curious about experimenting with various other bags and quilts, but even most quilts with similar temperature ratings only weigh an ounce or two (< 60 g) less than the UltraLite. Its 17 ounces of 850+ fill power down seem to supply more warmth than bags with 20°F EN lower limit ratings. To note, the WMB uses a continuous horizontal baffle that surrounds the body. For example, I used a 0° military down bag for years, while my hunting partner skated with a much lighter bag on many a sub-zero night. I pulled the bags from the tent and laid them out in a steady drizzle. The bag incorporated Quixdown®, a revolutionary treated down that is essentially waterproof. So I’m forced to either guess, or rely on Rokslide members who’ve owned the product much longer than me. Two-and-a-half hours later, with several puddles inches deep on each bag, I carefully tipped them so the water ran off, not into the hood openings. When compared to its more distant competitors in the budget backing sleeping bags, the UltraLite and all the other bags in the standard backpacking review are relatively small.

The KUIU Super Down includes a full hood and halo, and shoulder & zipper baffles to minimize heat loss. The absence of an organizational pocket or additional venting zippers helps this bag save weight. Compared to the adjacent cup filled with regular down, the Quixdown® maintained it’s loft while the regular down clumped into the bottom of the cup. Western Mountaineering Sleeping Bag Review KUIU released their Super Down Sleeping Bags in 2014. He’s killed four bucks over 200 inches in the last 15 seasons, mostly on easily-obtained tags. I think that is why this bag performed so well in this test. My best guest is that the hydrophobic Quixdown® did it’s job of repelling the water so the few drops ended up in the bag and not in the down. You can see the features of that bag here.

The Velcro: The UltraLite has a small velcro strip at where the top of the zipper meets the hood. This prevented me from completely zipping the hood over my face.

Not freezing, just a slight chill—enough to keep me from falling back to sleep. You can purchase either here, Or if you go the Western Mountaineering route, Rokslide Sponsor Seek Outside has the Badger MF here, If you’d like to ask questions or read other Rokslide members’ experiences, click here. Robby Denning started hunting mule deer in the late 1970’s, only missing one season in 35 years. I pulled out my phone and checked the weather. GearLab is reader-supported. We only make money if you purchase a product through our links, and we never accept free products from manufacturers. The Western Mountaineering UltraLite is my go-to sleeping bag for three-season trips into the mountains (the keyword here being “sleeping bag” – we're not talking about quilts here). I tested the two bags in the following areas: For both bags, I used the EXPED Megamat Lite MW with an R-value of 5.3, rated to -4°, and a small down pillow. Western Mountaineering class the Apache MF as a 2-3 season sleeping bag that ‘pushes the bounds’, in British terms though, we think it’s somewhat warmer than that description suggests and we’d look at it more as a lightweight, UK winter bag – it’s rated to -10°C with an extreme rating of -29°C, so should be capable of handling most UK winter nights just fine. When you click on links to buy products we may earn money to support, Best-in-class warmth, legit draft collar, light weight, exceptional loft, Really pricey, kind of bulky, awkward hood closure. There are “integrated flow gates” in each baffle that  keep the down from shifting and creating cold spots.

I've never really felt that it's been necessary and it can be a little strange closing it up all the way while inside the bag, but it's fine, I guess. If your budget lets you shop for the absolute best backpacking sleeping bag, you will likely end up with a choice between Western Mountaineering and Feathered Friends bags. Western Mountaineering does not use any hydrophobic treatments on their down (which is ethically-sourced), stating on their website that they believe the “performance enhancements of hydrophobic treatments on high quality down are widely overstated.”, I used the UltraLite hiking 1,000 mi / 1,600 km on the Pacific Crest Trail and on numerous shorter trips including the Wonderland Trail and the Lowest to Highest Route. On colder nights moving more feathers above your body will ensure more heat is trapped inside.