This bag will knock your socks off! How can it be so warm and comfortable and stuff into such a small stuff sack (included). Let it storm and let the wind blow because this bag will keep you toasty down to 15 degrees. With build in Flex(TM) between the shoulders and knees, you get the comfort and thermal benefits, while saving precious ounces. Continuous baffling and a draft tube contain 800-fill goose down, the warmest, lightest insulation available. If every ounce counts and every degree of warmth is a godsend, this bag is for you!