Sleep Master exceptionally comfortable 8 memory foam mattress for a better night's sleep. Memory Foam support helps to keep shoulders and hips in alignment and offers luxury that helps relieve pressure points, so you get the sleep you need for better health. This 8 mattress (4 base layer, 2 super soft foam, topped with a 2 thick layer of premium-quality memory foam) is ideal for back and side sleepers. All Sleep Master memory foam mattress are made with BioFoam TM to minimize the use of petrol based chemical oils, and Evergreen, real green tea extract, to help neutralize odors. ActivCharcoal , made from purified charcoal, is also included to help absorb moisture and odors as well. Sleep Master memory foam mattresses also contain CertiPur-US certified, flexible, polyurethane foam and offer a limited 5 year warranty. Compression technology allows for Fedex/UPS delivery. Meets all FR standards. Please allow a full 48 hours for it to fully expand. Memory foam is resistant to dust mites and naturally antimicrobial.