Alpinism is the ultimate sport in which everybody is a winner. An alpine school of self-discipline, maneuvering within your limits, belayed and secured by friends you trust......pushing your limits constantly. In this high altitude school, you learn to know your limits up against forces out of your control. In winter the conditions are even more at the limit. The Thor sleeping bag is designed as a winter high altitude expedition bag. The Thor design follows the Odin design but uses slanting baffle walls allowing stuffing the bag with the maximum of down. The Odin uses vertical baffles. The Thor is filled with totally mature and specially selected Gray Goose down 95/5 and can withstand temperatures found only at the ends of the world (-50 F). The Thor is also made from 27 down filled compartments compared to the 26 compartments of the Odin. Otherwise they are identical.