 It's possibly an adjustable base. It's sleeping cool, sleeping warm, whatever you need to do. And all we ask in return is that when you're ready to look for your next sleep system, you give us a try. Just shop one of our stores, see what you think. All locations are at MattressExpressNY.com. MattressExpressNY.com. There's more information there, too. You can always email me at PillowTalkQuestion at gmail.com.