The HI96720 Calcium Hardness Portable Photometer combines accuracy and ease of use in an ergonomic, portable design. A user can accurately determine the concentration of calcium hardness within a 0.00 to 2.70 mg/L (ppm) range using the HI93720-0 ready made reagents. The HI96720 offers many advanced features including the exclusive CAL Check™ function used for performance verification and calibration of the meter.