The 4-in-1 City Water Check for water quality testing is specifically designed to measure the major parameters in municipally treated drinking water. Accurate and reproducible results for pH, Total Alkalinity, Total Chlorine, and Total Hardness are achieved in less than 30 seconds without sacrificing cost. The 4-in-1 City Water Check water quality test is the quickest and easiest way to make sure your drinking water is safe.