Our superlight backpacking bag is now built with Primaloft Gold with Cross-Core, a mid-loft ultralight insulation that retains much of its insulating ability even when compressed. It's an incredibly light, compressible and comfortable sleeping bag.
This is the only sleeping bag in the world to feature Cross-Core, an industry-changing innovation that fuses NASA-developed aerogel technology with existing PrimaLoft Gold insulation, for more warmth without adding an ounce of weight. Sean McCoy, Managing Editor of GearJunkie.com had this to say: “Why is this a big deal? Well, aerogel is the lightest insulator on Earth.” It allows us to build a roomy, comfortable rectangular bag that's more than light enough to take backpacking.