For Calcium and Total Hardness determination by EDTA Digital Titrator titration. Ranges: 10-160 and 100-4000 mg/L as CaCO3. Reagent Set Contains: Buffer Solution (Hardness 1), CalVer 2 Calcium Indicator Powder Pillows, ManVer 2 Hardness Indicator Powder Pillows, Potassium Hydroxide Solution (8 N), EDTA Titration Cartridges (1 each) (0.800 and 0.0800 M).