a swag :-)

"A modern swag is a waterproof canvas sleeping compartment that is sometimes insect-proof. All swags come with a foam mattress, and can comfortably be slept in with the addition of a pillow and sleeping bag. When rolled up the swag is relatively lightweight and compact, making it ideal for storage and transport. It is typically easy to erect and roll up can be done quickly."
(http://en.wikipedia.org/wiki/Swag_%28bedroll%29)

Here's a few pics I found on the internet...might make more sense to you then :-)

Rod has one like this

but mine's a bit fancier and looks like this...well, it's meant to.
Rod picked it up at a garage sale and it didn't have the poles with it, so really it lies flat like his.

and they roll up like this -
that's what's on our roof rack, if you look closely