Brand: Sierra Designs
Model: BTU -5
Best Women’s Bag
Here’s a persuasive testimonial: One Alaska tester laid this 5°F bag on snow next to a creek, awoke during the night to a layer of frost on the shell—then snoozed soundly till morning. The proprietary Drizone waterproof/breathable shell fabric keeps the weather out, the zipper’s insulated draft tube prevents drafts, and the 600-fill down provides ample insulation for average-to-warm sleepers at temperatures right down to the bag’s rating.
And because women’s feet tend to get cold, the Solar Flare features a trim, efficient foot box with extra down and a cozy fleece lining (and zippered vent). “It’s a combo that works,” says our tester, who slept with only a pair of socks on her feet in subfreezing temps. Through the chest and shoulders, the bag has ample space to spread out and organize winter extras like layers, hand warmers, and a hot water bottle.
Extra insulation in the hood also boosts warmth and, when cinched down tight, it eliminated the need to wear a hat. The Solar Flare compresses to volleyball-size. Bummer: The hood and draft collar cinch with an exterior cord, which testers found difficult to grab in the dark. (Guys, get the Trade Wind.) $319; 3 lbs. 1 oz.; 5°FGreat for cold weather camping, the BTU -5 has a jacket style hood for maximum heat retention and a microfleece lined foot box for extra warmth and comfort. A Funk Off treatment on the liner keeps this bag smelling fresh on long backcountry trips.