The Comfort Tech 3” Foam & Fiber Mattress Topper Featuring Serene Foam is designed for true bedtime bliss. Serene foam offers enhanced support, is not temperature-sensitive, and reduces motion transfer, helping lead you to a more peaceful night’s sleep. The plush fiber-filled outer cover features COOLMAX moisture-wicking technology. Serene Foam is CertiPUR-US certified. Serene is a registered trademark of Carpenter Co.; Comfort Tech is a trademark of Carpenter Co.; COOLMAX is a registered trademark of The Lycra Company; CertiPUR-US is a registered certification mark of Alliance for Flexible Polyurethane Foam, Inc.