Kills bacteria 2 ways with a low level of chlorine and FROG Sanitizing Minerals. Minerals last 4 months, SmartChlor lasts up to 4 weeks and flips when empty. Ideal for 600 gallon hot tubs. Uses up to 75% less chlorine and maintains a consistent low Free Chlorine level, water is Cleaner, Clearer, Softer and Easier to take care of. Uses SmartChlor, a patented chlorine formula that self-regulates on demand for continuous crystal clear water, giving you peace of mind. Flips when empty, making maintenance easy. Shock only once a month with FROG Maintain, the recommended non-chlorine shock. With no chlorine, there is no Cyanuric Acid buildup that causes hard-to-manage, irritating water and frequent draining and refilling. Mfg : KING TECHNOLOGY INC. Product Line : Spa Chemical Sanitizers. Package includes: 1 sanitizing system, 30 test strips, 1 jump start, & 3 replacement cartridges. 3 pack SmartChlor EPA registration number 53735-14. Sanitizing System EPA registration number 53735-11. We will respond to you within 24 hours and do our best to help you out!