The present invention concerns a two-person sleeping bag formed by two single sleeping bags each mainly comprises an outer panel made from moisture-proof cloth, and a warm lining disposed inside the outer panel. The edge portion of the outer panel is provided with an outer zipper and an inner zipper...http://www.google.no/patents/US5005235?utm_source=gb-gplus-sharePatent US5005235 - Two-person sleeping bag formed by two single sleeping bags
