The Serta Perfect Sleeper Ultimate Gannon Extra Firm Mattress combines some of Serta's latest comfort technologies with a state-of-the-art steel coil innerspring support system. Individually wrapped steel coils balances body-hugging comfort with outstanding support for your body. The coils are then surrounded by a foam encasement that supports the edge of the mattress giving you full use of the surface. These mattresses are an ideal solution for those who prefer the look and feel of a traditional mattress with the benefits of advanced comfort and support features. With a layer of Cool Action™ Gel Memory Foam to help dissipate heat and relieve pressure, you'll be able to get the rest you need. This mattress has several layers of firm foam, providing an extra firm sleep surface for someone who prefers a quality, very solid mattress with some surface softness.