100% Polyester Easy Sleep: Our 12-Inch Gel Memory Foam Mattress in a Box offers great support, cooling comfort, convenience, and a clean design with porous, open-cell memory foam that meets CertiPUR-US program standards for performance, emissions, and durability Easy Set Up: Simply take your twin XL mattress out of the box and enjoy watching it decompress; Jumping, walking, and sleeping on your twin XL memory foam can speed up the process; Designed for a platform bed, this mattress is adjustable bed friendly, too