LL Bean has just announced a new sleeping bag that might just be a game-changer in the Down Vs Synthetic debate that has been raging on forever. How so? It’s the first sleeping bag to use AeroGel. AeroGel is a synthetic substance derived from a gel (can be silica, or carbon, or several others) that weighs practically nothing, which is why NASA uses it as insulation in their spacesuits. It is quite literally one of the lightest solids ever known, composed of 95% air. LL Bean went ahead and infused it with PrimaLoft Gold, resulting in a super lightweight yet super warm insulation they call Cross-Core Technology, that is also 35% recycled material. They’ve already got a whole line of Cross-Core clothing, but this is the first sleeping bag to use it.
As a result of this new Aerogel, the LL Bean Ultralight Sleeping Bag is just that – ultralight, weighing only 1 pound, 15 ounces, yet rated to temperatures down to 20 degrees. It actually comes in three models – 35-degree and 20-degree mummy bags, and a 20-degree rectangular bag. It’s super-compressible without losing much of its insulating ability, and also water-resistant; you can roll it up to the size of football and stash it in your pack. For a synthetic, it’s pretty warm without the bulk. The shell is a 20-denier nylon synthetic that is durable and with a hint of water-resistance.
The cut and design are pretty good, too; the cut is roomy, with lots of shoulder room, while the half-length zipper lets you leave it open a bit for venting. The trapezoidal footbox is designed to leave extra room for extra layers. Nothing too fancy – just a traditional mummy bag with a super warmth-to-weight ratio. Overall, the LL Bean Ultralight Sleeping Bag will make a great, lightweight all-rounder sleeping bag for all but the coldest of winter exploits.