Gear Review: Western Mountaineering Summerlite Sleeping Bag

Western Mountaineering Summerlite sleeping bag.
Western Mountaineering Summerlite sleeping bag

Ultralight Sleeping Bag
Western Mountaineering Summerlite
$410, 1 lb. 3 oz. (regular)
Sizes: short, regular, and long ($420)

The lightest sleeping bags for summer camping—meaning for temperatures from the 50s Fahrenheit to around freezing—rarely include features like a hood, a draft tube, and a two-way, full-length zipper. The Summerlite has all of those while weighing in at barely north of a pound and remaining true to its 32-degree rating. On a weeklong, late-March trip in southern Utah, I slept in it for nights of car camping and backpacking in the Dirty Devil River canyon, when the low dipped into the high 20s, and found it warm, spacious enough, and supremely packable.

Western Mountaineering Summerlite
Western Mountaineering Summerlite

With 10 ounces of 850-fill down feathers packed inside continuous baffles that encircle the bag, the Summerlite’s four inches of loft looks pretty fat for a summer bag. Continuous baffles are simple fabric tubes enwrapping the bag, within which you can shift down feathers, moving them to the top or bottom side of the bag, depending on how much warmth you need. I did not experience any unwanted migration of feathers—although that’s more common with continuous baffles than other types of baffles (and down can clump and distribute unevenly if you wash a bag with continuous baffles and don’t dry it properly). Unlike with some lightweight bags, the Summerlite has a thick, insulated draft tube inside the zipper to keep out drafts. The full-length zipper let me ventilate on nights in the 40s; you can also open it up enough to use it almost like a quilt, with your feet tucked inside the foot box. The zipper moves smoothly, and when it occasionally snagged briefly, I could easily pull the ulralight fabric out of the zipper.

For a lightweight mummy, it has good space—enough to get dressed inside. I like the 59-inch shoulder girth, which is thermally efficient, as a mummy bag should be: It warmed up in seconds as soon as I slipped inside. But I could also partly extend my arms while sleeping on my side, so that when I did seal the bag up tight on colder nights, I didn’t feel shrink-wrapped. But I’m of average build; broader people might find the bag snug. I could close the adjustable hood up snugly, leave it wide open, or micro-adjust the face opening within a wide range.

Hi, I’m Michael Lanza, creator of The Big Outside, which has made several top outdoors blog lists. Click here to sign up for my FREE email newsletter, or enter your email address in the box in the left sidebar or at the bottom of this story. Click here to get full access to all of my blog’s stories. Follow my adventures on Facebook, TwitterInstagram, and Youtube.

Western Mountaineering Summerlite hood
Western Mountaineering Summerlite hood

The bag packs into a one-ounce stuff sack that’s only slightly larger than a bread loaf. Construction is excellent and the bag should last many years. The first quality sleeping bag I ever bought was a Western Mountaineering, and I got a quarter-century of use out of it without the bag losing any loft or anything breaking (and I handed it down to someone who will get more years out of it).

One demerit: The hood adjustment strap hangs in the face of side sleepers. Still, the Summerlite is one of the lightest and most packable summer bags you will find that’s fully featured and built to last, and one of the best choices out there for ounce counters.

BUY IT NOW You can support my work on this blog by clicking this link to purchase a Western Mountaineering Summerlite at

See all of my reviews of sleeping bags that I like and all of my reviews of backpacking gear and ultralight backpacking gear, and my articles “Pro Tips: How to Choose a Sleeping Bag” and “10 Pro Tips: Staying Warm in a Sleeping Bag.”

Tell me what you think.

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NOTE: I tested gear for Backpacker Magazine for 20 years. At The Big Outside, I review only what I consider the best outdoor gear and apparel. See all of my reviews organized by categories at my Gear Reviews page.

—Michael Lanza

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