Sealy uses Individually Wrapped SealyStability™ Encased Coils for customized support as well as reducing motion transfer. With the addition of the exclusive CoreSupport™ Center, you'll feel the support for your core and and back, letting you wake up refreshed and pain free. The Coils are Encased with high density foam to firm up the edge, giving you full use of the mattress surface. Layers of SealySupport™ Firm Foam, cushion you firmly yet gently. A good mattress for a back sleeper.