The Ezee Kleen 2.5 is designed for offices in geographic areas having tap water dissolved mineral levels < 100 PPM (mg/L) or offices using low volumes of water. For geographic areas having tap water dissolved mineral levels >100 PPM (mg/L) or larger offices consider the Ezee Kleen 2.5 HD 4-Stage Ultra Clean Water System. Contact Oasis Dental Group Inc. for assistance in determining tap water dissolved mineral levels and the appropriate unit for your office.