Survival bags were a response to the needs of mountaineers and UK hikers, particularly in the Scottish Highlands. Single person units are available, but the multi person units work far better. As a sad example research the sinking of the argentine cruiser General Belgrano during the Falklands conflict. Rescuers found many liferafts with full complements alive. liferafts holding only a few were all found deceased from hypothermia. As stated, the units provide protection from wind and rain chill. The only insulation will be your own body heat and clothing. Fjelldukens are well made units. They are also extremely expensive and the swedish makers presently disinterested in marketing any outside of Europe. These are vastly superior to squatting in a military poncho with a candle between your legs! As a note: bothy is gaelic for a intimate rustic location of poteen drinking and listening to music. Think Star Wars Cantina or the tavern in LOTR. <img src="/images/graemlins/grin.gif" alt="" />