* DI (de-mineralize) resin refills * The bag contains up to 3 refills, or about 16 ounces of DI resin. It is able to process on average about 1600 gallons of RO water * Nuclear grade with color indicator: for production of demineralized water of high purity, silica free. * When the resin is used up, the green color resin will change to brown color. It will give you 0 ppm TDS, Conductivity attainable less than 0.1uS/cm or resistivity of close to 18 meg.ohm