Designed in Japan, the Ofuton Sleeping Bag is made of high-performance ammonophoro fiber insulation that retains warmth in temperatures as low as 41F, while the Deobrain processing ensures fabrics retain antibacterial properties. Use the Ofuton Sleeping Bag for outdoor excursions from spring to fall. The bag features a modular dual zipper to serve as both a sleeping bag and a futon. Pair with the Inflatable Mattress 2.5 for an added layer of comfort or explore the Ofuton Sleeping Bag, Wide LX for warmth in temperatures as low as 37F.