These technical, ultralight bags are designed for adventures where every ounce counts, each nook and cranny in your pack is accounted for, and you depend on the performance of your sleeping bag like you would a harness, helmet, or beacon. The "Fly Creek of sleeping bags," our Star Fire UL series features the ultimate 850 fill power DownTek water-repellent down, and are built with a superlight, high-tear strength shell that also protects the inside footbox. Body-mapped baffle construction optimizes thermal efficiency creating the lightest, highly compressible bag for your most remote of overnight adventures.