This cartridge contains a proprietary, FDA-approved formulation that, together with a patent-pending distribution system, makes this salt-free water softener your best solution. Enjoy healthy, salt-free soft water that not only prevents, but also removes hard-water buildup that clogs and corrodes your water heater and other home plumbing fixtures and appliances. This amazing, compact system uses a process to condition all the water throughout your entire home. The nuvoH2O Studio system uses revolutionary technology to lower the PH level of water based on the basic scientific process of chelation in which the metal ions causing hard water, principally calcium and magnesium, are bound to the chelating agent in nuvoH2O's FDA-approved, proprietary formulation, which keeps the minerals soluble and unable to cause hard water problems. The resulting water is soft and healthy for all of your household uses, including drinking, bathing, washing, and lawn and plant watering. Studio cartridge Treats water for about 4-6 months The cartridge contains a proprietary, FDA-approved formulation This cartridge does not fit Home System nor the Manor System Please see images and dimensions prior to purchase Product ID 114543922