Innerspace Sofa Sleeper Mattress Replacement -52 X 72 X 4.5 Inch High Density Polyurethane Foam &ndash; Comes with manufacturer's 30-day no-obligation sleep test. MATTRESS ONLY, DOEST NOT INCLUDE SOFA Finally a solution to the uncomfortable sofa bed mattress! Ships rolled via UPS. Expands to 90% in 30 minutes and to 100% within 48 hours. 4.5 Inch High Density Polyurethane Foam-Quilted stretch-knit zipper removable cover No motion transfer between sleeping partners -Built-in FlameWatch flame retardant technology Manufacturer's 30-day no-obligation sleep test-Manufacturer's 10-year pro-rated warranty