SUNPURITY® SUNDANCE® Spas' mineral spa sanitizer leaves water clear and soft. An alternative to chlorine when used in combination with MPS (monopersulfate), the SUNPURITY® cartridge fits into the bromine dispenser of the 880 and 780 Series spas' filter bays. It reduces the potential for unpleasant odors and residue lines, and can be used with your ozone system. Lasts up to four months. Not available in Canada or Europe. Item #6890-780 Note: The SUNPURITY® requires only a small maintenance dose of non-chlorine oxidizer and should not be mixed with bromine and bromides. The SunPurity cartridge is not compatible with biguanides such as SoftSoak or Baqua.