This meter is vital to test the initial quality of your water and also measures the amount of dissolved silver during the electrolysis process. This item is not included with The SilverLungs™ Generator (Base Kit) to accommodate those who already own a proper water test meter. The water meter (is) included with The SilverLungs™ Generator (Deluxe Kits) along with our most popular accessories. The water meter comes pre-calibrated saving time with initial setup.