Night Therapy’s Memory Foam 8 Inch Mattress and BiFold Box Spring set offers an excellent sleep solution for a healthy night’s sleep. Night Therapy Memory Foam is open cell memory foam offering improved airflow movement while providing a customized level of support. A mattress is a large, rectangular pad for supporting the reclining body, designed to be used as a bed or on a bed frame, as part of a bed.Mattresses may consist of a quilted or similarly fastened case, usually of heavy cloth, that contains materials such as hair, straw, cotton, foam rubber, or a framework of metal springs. Mattresses may also be filled with air or water. .