The Jacuzzi ProClear Mineral Spa Sanitizer has been designed to work exclusively in Jacuzzi hot tubs by utilizing water flow through the Jacuzzi filter system. The cartridge easily snaps into the lid of your J-300 and J-400 Collection hot tub filters. The Jacuzzi ProClear Mineral Spa Sanitizer needes to be changed every 4 months.Features of the Jacuzzi ProClear Mineral Spa Sanitizer: Reduces potential for unpleasant odors and scum lines.When used with chlorine, purifies water, kills bacteria and algae more effectively and much faster than chlorine alone. Can be used with ozone systems and lasts 4 months. A natural process that carries out 3 functions: disinfection, algae prevention and clarification. Should not be mixed with Bromine and bromides. Not compatible with Biguanides such as SoftSoak or Baqua.