Hands-on Gear Review
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Pros: Best down, materials and construction; lightweight; includes a neck baffle to seal in warm air.
Cons: Relatively uncomfortable hood, weak neck baffle velcro comes undone easily, top quality fabric only on top- not bottom.
Best Uses: 3-season backpacking and camping.
Manufacturer: Western Mountaineering
The Western Mountaineering Ultralite 20 is a lightweight, highly compressible, and well-featured three-season bag. It's one of our favorite traditional style sleeping bags on the market and it competes with the Feathered Friends Hummingbird 20 for the title of the best hooded three-season bag. While both of these top performers have the highest quality 850+ fill down, there are three primary differences that separate them. First, the Ultralite's cut is a bit more spacious and adds 3.5 ounces more than the Hummingbird. Second, the Ultralite is equipped with a neck baffle and the Hummingbird is not. (If all other factors were equal, this would maks the Ultralight warmer.) Third and finally, Feathered Friends offers the Hummingbird in 850 or 900-fill down, two different fabric options each with a variety of colors, and one of four different cuts. The latter factor is most important- getting a cut that fits your body maximizes thermal efficiency and reduces weight. Thus, depending on your body type and size, we believe the Feathered Friends Hummingbird will offer more performance.
Consider a quilt!
Traditional sleeping bags with zippers and hoods have fixed girths, which is a significant limitation for backpackers and climbers that cross multiple climates or wear clothing inside the bag. We've found that quilt style sleeping bags are much more versatile, lighter, and more comfortable in a wider range of conditions. Our testers much prefer quilts for multi-day backpacking and climbing trips. Check out our comprehensive Backpacking Sleeping Bag Review to see how the Ultralite compared to other traditional bags and see the Ultralight Sleeping Bag Review for our favorite bags that prioritize weight savings.
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OutdoorGearLab Editors' Hands-on Review
New Review Coming: Fall 2015
Our reviewers are currently hard at work testing the latest version of the Western Mountaineering Ultralite 20! Check back this fall for a new review!
The Western Mountaineering Ultralite 20 is a wonderfully light, compressible, and well-featured twenty degree bag. Undoubtedly one of the best bags in its class, the Ultralite utilizes 850+ fill European goose down, the highest quality available.
Beyond the high quality down, the Ultralite also boasts a stiff anti-snag zipper and a well-designed neck baffle that keeps hot air in and cold air out. The neck baffle is positioned well, roughly between the shoulders and chin, and constricts in an unobtrusive way that effectively seals out unwanted cold air. We felt comfortable and cozy even when the neck baffle and hood were fully cinched.
The Ultralite is made of top quality fabrics. The bag's blue top piece is a 20 denier, 10 filament, 380 thread count ripstop nylon that's DWR treated. The inside and bottom are made of 20 denier tafetta, allowing for increased breathability.
The Ultralite weighs 29 ounces, which establishes it as one of the lighter traditional three-season bags we've reviewed. Beyond the high quality shell material and excellent down, the bag's trim fit is the key to weight savings. This bag is for trim people. Its narrow cut makes it more efficient at keeping you warm and saves weight at the same time.
While we really appreciate the addition of a neck baffle, and value the comfort of the one this bag has, we were troubled by its small and ineffective velcro closure. A violent shuffle or an attempt take an arm out of the bag will break the Velcro closure. This problem is not unique to the Ultralite: it's also found on all other Western Mountaineering bags we've tested (Antelope MF and Versalite). Western Mountaineering should redesign their neck baffle closure with snaps. The Marmot Plasma and Feathered Friends Hummingbird offer significantly better baffles closures.
As for weight, the Ultralite is light, but definitely not ultralight. Other bags are much lighter and warmer for their weight. The ZPacks 20 Degree bag, for example, weighs only 17 ounces and is nearly as warm as the Ultralite. That's 12 ounces lighter!
We highly recommend quilt style sleeping bags because they offer more warmth for their weight and are more versatile than traditional sleeping bags with fixed girths.
A minor drawback: the Ultralight only has Extemelite fabric on the top of the bag, not the top and bottom. This fabric is very very good and we wish Western Mountaineering used it for the entire exterior shell-- it would increase durability and weather resistance. All other top-tier sleeping bags are constructed entirely or almost entirely of the same shell fabric.
Backpacking and climbing.
A good value for a fixed girth bag.
Western Mountaineering Summerlite
Western Mountaineering Alpinlite
Western Mountaineering Antelope MF
— Chris McNamara and Max Neale
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OutdoorGearLab Member Reviews
Most recent review: May 7, 2015
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