DynastyMattress 4.5-inch Gel Memory Foam Sofa Mattress-TWIN Size 4.5 Inch thick. 2" HD Gel plush memory foam and 2.5" Base Foam Support sofa bed mattress Plush sofa bed sleeper mattress; ideal for relief of back pain. Ships compressed for easy delivery and set up. Fit into small bedrooms with ease. Memory foam conforms to body, aligning neck and spine creating optimal sleep environment. Gel Foam is CertipurUS Certified. With Fire Barrier, free of any harmful materials. 5 year warranty. TWIN Size:72 x 33 x 4.5 inches