N2 DuoClear 35 SCG System w/o Cartridge DuoClear, the complete automatic water treatment system for hygienic, clear and more natural water throughout the season. - Super chlorination: when intensive use of pool and/or heavy rain is expected. - Less chlorine: increases the life expectancy of the electrode. - Balanced water: reduces fluctuations in pH level - Autonomous: an intelligent control unit for an autonomous system. - No maintenance : self Cleaning electrode by reverse polarity.