As far as survival situations goes, the hood portion of the (recently recalled) EVAC-U8 smoke hood is--was--made of transparent Kapton, kind of like cellophane gift wrapping. Not surprisingly, the EVAC-U8 is made by a subsidiary of DuPont. The hood can be folded down very small, so the whole unit is the size of a can of soda. That's smaller than its bulkier competitors, so that was one selling point of using Kapton. *sigh* Too bad they found something potentially dangerous with the CO filtration in the EVAC-U8. I still don't want to send mine in.