The Isotonic 4” 5-Zone Mattress Topper Featuring Isotonic+ Memory Foam is designed with cool channel ventilation technology to help lead you to a better night’s sleep. The plush yet durable memory foam provides enhanced pressure relief and reduces motion transfer. Isotonic+ memory foam features IsoFresh odor-neutralizing technology and is CertiPUR-US certified. Isotonic is a registered trademark of Carpenter Co. IsoFresh and Isotonic are trademarks of Carpenter Co. CertiPUR-US is a registered certification mark of Alliance for Flexible Polyurethane Foam, Inc.