The Caribou may be the most versatile bag on the market. The bag comprises two separate summer weight sleeping bags, which can zip together to make one double sleeping bag. In colder weather, the inner bag can be zipped into the outer bag to form a single very warm bag. The extra large size makes this sleeping bag a great choice for the larger person. The Caribou 3 in 1 sleep system comes with anti snag zipper and in a printed storage/display cube.