I googled the name, and it appears they are used by some manufacturers in some of the full-on travel trailers and fifth wheels. I'm wondering if the full might be the cat's meow in a 6X12 cargo.
It almost seems like one of those "too good to be true." Springs instead of wood. Only 8-inches wide folded up on the wall!

A comfortable bed is top priority in my cargo conversion, while still leaving space for some small conveniences and comforts.