Aerogel was invented by NASA, earning a reputation as the world’s lightest solid. It first came onto the outdoor scene because of its incredible insulation abilities but it has major limitations including friability, sensitivity to water, and lack of breathability. PrimaLoft brought the substance into the spotlight with its creation of PrimaLoft Gold Aerogel — a fabric that encapsulates the substance and allows for widespread use across the outdoor industry. Now, L.L. Bean has teamed with PrimaLoft to introduce the first Aerogel-insulated sleeping bag.

PrimaLoft first introduced NASA’s trademark Aerogel insulation to the market of outdoor apparel with Helly Hansen’s Lifepocket. The company utilizes PrimaLoft Gold Aerogel in the cell phone pockets integrated into many of their ski and snowboard jackets in order to maintain battery life. But PrimaLoft didn’t stop with PrimaLoft Gold Aerogel — the company developed a product that would integrate Aerogel into fabric.

PrimaLoft Gold Aerogel with Cross Core is the first product to combine Aerogel with fiber technology necessary for use in batted insulation. This invention allows for use of Aerogel in products that demand a degree of breathability. While PrimaLoft encapsulated the membrane as with the PrimaLoft Gold Aerogel, this new product boasts greater breathability thanks to the lofted element of the fibers.

L.L. Bean’s Ultralight Sleeping Bag features PrimaLoft Gold Aerogel with Cross Core and is available in a few different models. The line includes 20- and 35-degree mummy bags and a 20-degree rectangular bag. These products boasts a weight similar to comparable down bags, although they don’t compress quite as well. The Regular 20-degree mummy weighs in at 1 pound, 15 ounces. Additional features include a 20-denier ripstop nylon shell, small inside shoulder pocket, and trapezoidal foot box for added comfort.

L.L. Bean is the exclusive partner with PrimaLoft’s developer for the insulation for 2018, according to GearJunkie. You won’t just see the insulation in the sleeping bags but across a whole line of products including coats and jackets. For 2019, the insulation will be made available industrywide. This year’s Outdoor Retailer and Snow Show showed a widespread interest in the adoption of Aerogel technology. The substance is being utilized in boot insoles, toe caps, and glove fingertips — places where breathability isn’t necessary. You’ll see a release of more and more Aerogel products as the year progresses.

The Ultralight Regular 20-degree mummy bag retails for $220 while the Long version retails for $230.