Tube tents were also suffocation hazards that only lasted about 5 minutes before the cheap plastic was shredded beyond being able to be used. They let blowing rain in, were small and cramped and your feet stuck out the ends. I used them in Boy Scouts and they sucked. They did make a great "sweat lodge", though. Anyone who could spend the night in one woke up in a puddle of sweat and 10 lbs. lighter.

BF