Hbaid 8 inch Memory Foam and Innerspring Hybrid Medium-Firm Feel Hybrid Mattress， Our hybrid mattress is a perfect alternative to those that prefer the innerspring support and the memory foam mattress feel.CertiPUR-US certified memory foam and skin-friendly mattress fabric cover provide you a safe and healthy sleep. the wrapped innerspring coils move independently providing comfort and support for an undisturbed night's sleep. Hbaid mattress with ergonomic design fits all sleepers, whether you are side sleeper, back sleeper or stomach sleeper..Bed in a Box，Twin size mattress is compressed and packaged in a box makes it can be shipped to your door for easy set up. Notes: 1. Restore its shape in a few minutes after opening, please give it 72 hours to fully expand. 2. To guarantee the validity of your warranty, please follow the instructions in the manual.