A sleep upgrade you'll flip for. Thoughtful convoluted topper design promotes restorative relief plus versatile flipping options. The convoluted design means it has built-in peak-and-valley airflow channels that help promote airflow, plus cradles you gently (think: the same way an egg sits comfortably supported in an egg carton.) Designed with your greatest comfort in mind, this 4 in. topper is constructed of premium memory foam that conforms to your unique shape for the ultimate comfort and support a thicker topper option for even more cushioning. Plus, topper comes conveniently compressed. So you can decompress in minutes. Pair your topper with the Comfort Revolution Mattress Topper Cover (sold separately) to help hold your topper firmly in place. The soft-to-the-touch, polyester microfiber stretch knit cover provides a soft feel, plus serves as a protective layer to help prevent against general wear and tear. This quality cover is designed for easy care simply remove, machine wash and rest easy. Accommodates sleep surfaces up to 21 in. Convenience and comfort, fully covered.