Polyester 【RELAX IN PRESSURE-FREE TOPPER, RELIEVE BODY ACHES】If you wish to get the full gel mattress topper which offers cloud-like softness and support, choose Novilla mattress topper. Our 4 inch mattress topper full size designed with premium high-density gel memory foam which helps to balance gentle support with ample cushioning, less sagging, relieve common pressure points, and body aches caused by sinking into foam. 【COOLING FEEL, UNINTERRUPTED NIGHT’S SLEEP】Perforation and cooling gel help to increase airflow, improve breathability and regulate temperature, which helps to transfer heat away from the body and get rid of overheating. Meanwhile, gel-infused mattress topper can provide motion isolation for those who are sensitive to their partner's movements throughout the night. Be ready to wake up refreshed and energized every day!