I just got my 4" king mattress of memory foam. I have the retractable bed and it works great with the foam mattress on top of the GS mattress. Can't wait to use it, picked it up at Overstock but Costco and Wally World have them in any thinkness. Pal of mine says its the only way to sleep.
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2007 42' Friendship Quattro
2007 Liberty Toad
No Rodents
Kids raised and only barrow money
400 Cummins Bad Milage