Traditionally, all of the lightest weight bags are made with the extremely light ripstop nylons. We created our Western Mountaineering Caribou Down Sleeping bag to be lightweight, durable, and comfortable by using MicroLite XP. This 1 lb. 5 oz. mummy bag has a full length zipper and is cut wider than average for broader shoulders and a more comfortable fit. With its highly breathable taffeta fabric, the Caribou is a durable lightweight summer bag and a great choice for AT hikers. Size: 5ft 6in Length Rating: 35° F Loft: 3.5in Inside Girth (shdr/hip/foot): 63in /56in /39in Fill Wt: 9 oz Total Wt: 1 lb 4 oz Stuff Size: 6in x12in