Bought because we have a double sleeper sofa excellent (small space) 90 wide day and 180 at night. What sleep very comfortably! Still, the second bed was the mattress (changed following the damage of an incontinent cat). They began to make me a bit "crazy": always to push! Then the waning of my navigation, I discovered this wonder: no worries, it's magic. Easy to set up: under the mattress. A 120 is quite sufficient and can be reused. Thank you Amazon!