See full details at the Amazon listing: https://www.amazon.com/Zinus-Extra-iCoil-Support-Mattress/dp/B0134FXSWE
About this item General Note: Please allow 24 - 72 hours for your Mattress to regain its full shape. Any memory foam will expand faster in a warmer room. In cold temperature, at delivery, your mattress may take a bit longer to return to full sized from its compressed state.The expansion time of the mattress will vary as per the surrounding.Set Up: Simply take your mattress out of the box and enjoy watching it decompress. Jumping, walking, and sleeping on your mattress can speed up the process. FIRM SUPPORT, PLUS MORE - Our firmest mattress ever is engineered with heavier gauge steel independent pocket innersprings for added stability and extra firmness, ideal for stomach sleepers and plus-sized individuals SUPPORTIVE FOAM & POCKET SPRINGS - Soft comfort foam, durable high-density foam and motion-isolating independent pocket springs with a quilted jacquard cover offer a firm feel that’s perfect for stomach sleepers and those who enjoy a very firm mattress CERTIPUR US CERTIFIED - Highest quality foam is CertiPUR-US Certified for durability, performance, and content EXPERTLY PACKAGED - Our technology allows this mattress to be efficiently compressed into one box that’s easily shipped and maneuvered into the bedroom; simply unbox, unroll and this mattress does the rest, expanding to its original shape within 72 hours
