A suitsack is a powered coverall, intended for single person use, that serves as a local micro-climate regulator and sleeping shelter.
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The next stop on the itinerary was a place where we could get suitsacks: huge orange coveralls whose legs could be zipped together to make them into sleeping bags. These were made for people who hunted or scavenged in the far north. Each had a catalytic power unit built into it; as long as you kept some fuel in its bladder it would supply a modest trickle of power that was routed down the suits’ arms and legs to warming-pads placed in the soles of the boots and the palms of the mittens. New ones could be pretty expensive, but Yul had helped Orolo get a cheap one the other day. He knew of places where you could get used ones that had been fixed up, and he knew tricks for making them more comfortable.