The FROG @ease floating system* offers a self-regulating water care experience that is easier than ever. Enjoy fresh clean mineral water combined with SmartChlor?? technology that uses up to 75% less chlorine . maintains chlorine at lower levels . & reduces the frequent need for hot tub maintenance. The floating ball even turns over when your SmartChlor cartridge needs to be replaced. Start-up System Kit includes 1 Floating Ball with Mineral Cartridge . 1 SmartChlor cartridge for the floating system . 1 Jump Start package . and 1 bottle of @ease water test strips. Use this system in spas with a single filter or in other brand spas.