SleepBetter 2.5-Pound Density 4-Inch Memory Foam Mattress Topper, Full 4 Inches thick, 2.5 pound density Space Age memory foam supports head to toe Adjusts to your shape for maximum comfort Hypo-Allergenic Measures 50 by 72 by 4 SleepBetter is registered in the U.S. Patent and Trademark Office