we tuck the C-hoop into the folded mattress, before raising the bunk door.
and the outside mattress straps wrap around the C-hoop, then snap to the inside of the bunk door. then end of the mattress snaps to the other inside snaps of the bunk door.
this is how it works on a 2007 Roo, before they changed to the preattached canvas.
don't know how the mattresses are attached now.
and Zoe the Wonder Dog(R.I.P.)
'07 Roo 23SS pushing an '07 Chevy Avalanche
Equalizer WDH and Prodigy BC