Kerchiller™ are an innovative product designed to lower core body temperatures when worn around the neck, by cycling cooler blood through the circulatory system. Water activated, they require no refrigeration to be effective, and stay cool for DAYS at a time. Washable and reusable for years, Kerchiller™ effectively provide protection from the heat, and in addition, can be used as a soothing heat wrap by microwaving briefly. Simply re-soak as needed to reuse your Kerchiller™ neck cooler over and over.