The latest addition to Western Mountaineering's Extremelite Series is a wide sleeping bag made for side sleeping comfort, the Terralite. There are two zippers allowing this bag to mate with our mummy bags and the second zipper opens the bag up completely around the foot. With both zippers open this bag can make a fairly wide "camper van" comforter, but even when zipped up it is extremely comfortable. This is due to its wide girth through the middle of the bag, a design that side sleepers will find ideal.