The new Sealy 51162131 Basils firm twin xl mattress was developed to provide comfort that lasts year after year. Get the lasting comfort your body desires and the support it needs. We start with a soft breathable knit fabric to provide a great sleep environment. Classic Coils respond to your body and give resistance where you need it the most. OrthoZone II® Gel Infused foam provides another layer of comfort and stability you have come to trust from Sealy. New features such as the SolidEdge HD™ technology gives you more sleep surface and prevent the mattress from shifting side to side.