Serenia Sleep 4-Inch Memory Foam Combo Topper, King Perfect 4-Inch combination of support and memory foam comfort to revitalize sleep surfaces - King 74 x 77 inch 1-1/2-Inch Memory Foam comfort layer relieves pressure points and cradles the body 2-1/2-Inch high density foam support layer provides long-lasting support and revitalizes any sleep surface Open-cell cool memory foam sleeps cooler than traditional memory foam Temperature sensitive, hypoallergenic, spot clean only