Sleep Master 8-Inch Pressure Relief Memory Foam Mattress and Platform Metal Bed Frame/Mattress Foundation, Twin Mattress layers include: 2 memory foam (3 lbs. density), 2 super soft foam with pressure relief system, and 4 high density foam base. Steel bed frame eliminates need for a boxspring The mattress is shipped in a small box and can take up to 48 hours to fully expand from its compressed state. CertiPUR-US Certified Limited 5 year warranty