Brian, for my model year, the sofa is essentially a sliding platform on wich two cushions sit. The cushions are rectangular pieces of foam approximately 75"x34" for the seat and the backrest about 75"x14". Both cut from 6" thick foam. When the gaucho is pulled out, these cushions lie flat to make a bed. It sounds as though you may have more a problem with the structure of your sofa than a cushion problem. Are you able to remove the cushions to have a look at what is causing the sag?
Cameron & the Labradors, Kai & Samm
North Vancouver, BC
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