Brand: LL Bean
Model: UL Mummy
Here in Colorado, we tend to forget that a lot of the country doesn’t see frigid temps in the winter. For those regions—and for hikers everywhere braving wet shoulder-season conditions—this synthetic bag is just the trick. Its design infuses PrimaLoft Gold fill with aerogel, an extremely low-density solid that provides a ton of insulation without a ton of weight. The result: a synthetic bag that’s less than 2 pounds, and packs down to just larger than a football. One tester toted it on a three-week trip through the California Sierra, during which the bag kept him cozy down to 20°F.
The above-average 63.5-inch shoulder and 41.5-inch footbox circumferences result in a semi-rectangular shape rather than a more traditional mummy silhouette, making it one of the more spacious bags we tested. Caveat: Some testers reported chilled feet in subfreezing temps because of the extra room (stuffing a puffy in the footbox helps).
“It never lost any loft throughout my three-week trip. I’ve seen loft issues with other bags during extended expeditions,” says our California tester.
Weight: 1 lb. 15 oz.
Temp Rating: 20°F
See the entire Winter Gear Guide