Whether you are taking your Therm-a-Rest Fast & Light sleeping bag out into the alpine, the desert or snowy tundra, each and every bag was designed by our team in Seattle, WA. Since 1972, our engineers and product designers have considered every corner and detail of our products to bring you a better night outside. We take a closer look at the designers and philosophies that brought you the Polar Ranger, Oberon, Parsec and Space Cowboy sleeping bags. To experience the full line, visit our Sleeping Bags & Quilts page.

designing sleeping bags

The mandate sounds simple. Create a durable, ultralight and packable sleeping bag. Then, ensure that it protects adventurers from harsh elements and rugged terrain. While you’re at it, make sure the fill is responsibly sourced and that the price is right for a dirtbag mountaineer or skier.

While designing the Fast & Light sleeping bags, Jim Giblin and Katie Nash considered every possible thread, cut and filament. Every corner thoughtfully considered.

“Alpinists are deliberate with every piece of gear, from their cams and ice tools to their sporks, before heading up a climb,” said Jim. “We brought that same level of consideration into the design of each bag.”

They began by considering the specific needs of backcountry athletes. This range covered thru-hikers, bike packers, climbers and mountaineers. They even consulted some of the leaders in Arctic exploration for insight on dealing with extreme temperatures.

sleeping bag fabric

Katie said that, “we realize that the bigger the endeavor, the more the small details start to matter. When users are out in the hills, every minute of sleep and every degree of warmth starts adding up. The bags Jim and I designed allow adventurers to get the most out of their recovery and sleep. We weighed every design choice carefully and made zero compromises.”

One notable difference between the Therm-a-Rest line and other lightweight bags are the added comfort features. While Therm-a-Rest bags are some of the best in their class, they also have features like oversized draft tubes and a roomier fit. The design team realized that just because someone is an elite alpinist or a PCT thru hiker, doesn’t mean they wanted to be wrapped tightly in down and nylon. The roomier fit and SynergyLink connectors allow campers to move freely in their bags without exposing cold spots. The oversized draft tube ensures that heat is not escaping out of the top of the bag.

“Our bags not only keep you comfortable through the night, but also conserve energy and heat,” said Jim. “This means better rest and more energy when you wake up tomorrow morning.”

sleeping bag design

In order to keep the bags ultralight, Katie and Jim sourced high-powered, RDS (Responsible Down Standard) certified down to insulate the bags. This decision led these bags to weigh in among the lightest in their categories, a huge factor for our “fast and light” customers. The Nikwax Hydrophobic Down stays dry and retains loft to keep you protected in cold and wet conditions.

Katie and Jim’s commitment to comfort and “every-corner-considered” philosophy has produced a line of bags built for explorers that need to stay comfortable and energized while pushing deep into the backcountry.

This careful design and attention to detail allows us to put our Better Sleep Guarantee (only available in the US and Canada) on all Therm-a-Rest sleeping bags. Check out our full line of sleeping bags today.

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