The North Face Dark Star 0F (AZJC ) is a rugged, zero degree, synthetic expedition sleeping bag that provides dependable warmth for cold weather camping. The All New Dark Star Line of bags set the standard for expedition quality. Climashield Prism and Climashield Apex shingled construction keep you warm when the temps dip below freezing, and a rugged 20D Pertex shell is lightweight and tough as nails. The North Face knows that having enough room for your feet is as important as anything in a zero degree sleeping bag, and with a vaulted footbox your toes stay warm and comfy all night long. An ergonomic heat trap along with an expedition fit make this bag stand alone at the top of the mountain of quality. As if all this wasn?ÇÖt enough, the stuff sack doubles as a summit pack for lightweight ascents.