· For use only in certain hot tub models: Artesian Elite, Artesian Island (optional on Artesian Island Elite and South Seas); Marquis Crown (optional on Marquis Elite, Vector and Celebrity); Caldera Vacanza; and Hot Spring Hot Spot and hot tubs up to 600 gallons· For use only with FROG @ease In-Line Mineral Cartridge, both are prefilled for no mess, no guess and no stress. Together, the @ease system combines the proven FROG mineral formula with SmartChlor Technnology· Eliminates organic contaminants 2 ways with FROG Sanitizing Minerals that removes contaminants and SmartChlor – a unique, patented chlorine that self-regulates and maintains a consistent low Free Chlorine level. Say goodbye to constant monitoring· The FROG @ease In-Line System uses up to 75% less chlorine* so it’s easier on skin, hair, swimsuits and your hot tub’s surfaces. Not only is the water wonderfully soft, but it is also odor free· This system also needs shocking only once a month, or when draining and refilling your hot tub – making it so much easier than shocking after every use. You will save time and the cost of constant shock treatments