Gear Review: Deuter Dream Lite 500 & Sea to Summit's Reactor Thermolite Sleeping Bag

A 40° mummy that disappears inside a pack.

Everything about this bag is scant: its weight, packed size, and price. Even without a compression sack, this 40°F mummy squishes down smaller than a one-liter water bottle, so it disappears inside a pack. It’s stuffed with Polydown, a short-staple polyester fiber. (Short-staple insulation has filaments that are cut into small pieces to make it more compressible.) For one cold-sleeping tester, the thin blanket of insulation proved sufficient for summer nights down to 50°F in the high desert of Colorado National Monument.

A cinchable hood and zipper draft guard boost warmth when temps dip into the 40s. When the mercury rose, the full-length zipper offered head-to-toe venting. Our broad-shouldered, 5’11” tester found the bag’s dimensions to be “trim but comfortable.” The Dream Lite also proved useful for winter hut-tripping, when it kept testers warm in drafty, wood-heated yurts and cabins. Downside: The insulation and fabric (nylon tactel taffeta for the lining, and water-resistant ripstop nylon for the shell) delivered below-average breathability when humidity was high: Testers felt clammy unless the bag was unzipped at least partially. $79; 1 lb. 2 oz.; 40°F;


For extremely warm temps (around 70°F and above), skip the bag and go with a liner like Sea to Summit’s Reactor Thermolite. It’s made of stretchy Thermolite that breathes and wicks well, and can also be used to add more insulation to a winter system (about 10°F, says our tester). $55; 9 oz.;

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