Malouf Isolus 2.5" Gel Memory Foam Mattress Topper - FullISOLUS 2. 5" Gel Memory Foam Mattress Topper Full Sized Featuring a 2. 5" comfort layer of gel infused memory foam, this mattress topper offers superior cooling and provides relief from heat and sleeping pressures. Utilizing a pin core design, the gel memory foam is ventilated to increase air flow and regulate sleeping temperature. The soft, supportive consistency of the memory foam quickly conforms to the body, cushioning hips and shoulders.