Serta's Perfect Sleeper helps solve the most common sleep problems: tossing/turning, sleeping too hot or too cold, partner disturbance, and more. The Cozy Slumber Firm has 825 individually wrapped coils that balance body-hugging comfort with outstanding body support. HexCloud gel features strategically placed geometric shapes and rests above the coils to help relieve pain from pressure points. A foam encasement is placed around the border of the mattress to reduce edge roll-off and extend the sleep surface. This exclusive 2-sided mattress allows you to use each side half the time so you can periodically refresh your sleeping surface by flipping the mattress over.