3-Season Sleeping Bags Reviews

Editors’ Choice 2021: Big Agnes Sidewinder SL 20°F

Stop tossing and turning and get the backcountry beauty sleep you deserve.



2lbs. 4oz.

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Chances are you know a side sleeper. In fact, chances are you are one. According to Big Agnes, some 70 percent of us sleep that way. But in camp, that means we breathe into the hoods of our bags at night and periodically freak out when we get twisted up. If we try to roll with our bags we expose our backs to the cold, since many designers put less insulation on the downside of the bag where it is compressed by your body weight anyway. Well, good news, side-sleeping compatriots: There is now a bag just for us.

The Sidewinder nails a side-sleep design. Its hood opening and zipper are oriented so that they face the same way you do when you’re on your side, rather than being permanently situated “right-side-up” on the bag. The dimensions are slightly wider than a typical back-sleeper (61-inch circumference at the shoulder and 55 at the hip in the men’s version) because we tend to curl up a bit. Critically, there’s also a strip of synthetic insulation that wraps the hips and ankles to pad and insulate the parts of us that contact the ground most rudely. (The rest of the bag is stuffed with 650-fill down.) The tight-fitting hood is bliss when nights dip to the temp rating. “This bag felt like a sheath,” said our 6’2” executive editor after a couple of cold, 30°F November nights in Badlands National Park (he used the long size). “It moved with me as I rolled over to reduce pressure on my hips at night, but it never felt restrictive. I’m glad to not have to change my sleeping style to meet my equipment anymore.”

regular and long, women’s regular and petite