Serta ThermaGel Cooling, Pressure-Relieving Memory Foam Mattress Topper, 3 Inch, King,BlueSleep like youve never slept before on this mattress topper from Serta. As part of the Serta family of comfort solutions, this ThermaGel memory foam topper can improve any nights rest on top of virtually any mattress. This adaptable mattress pad conforms to the sleepers unique body shape to provide superior support for joints and pressure points while remaining breathable with ThermaGel particles to keep the sleeping surface cool all night long. ThermaGel is a trademark of Leggett & Platt, Inc.