Chlorine, total hardness, iron, and pH photometer: Free Chlorine: 0.00 to 2.50 mg/L, Total Chlorine: 0.00 to 3.50 mg/L, Total Hardness: 0.00 to 4.70 mg/L, Iron: 0.00 to 1.60 mg/L, pH: 5.9 to 8.5 pH - kit including carrying case and CAL Check standard