CS-AD1040 is a professional bench meter for pH, ORP (Oxidation Reduction Potential), and temperature measurements. Relative mV readings are also provided. Main Features of This Product Include: -Up to three-point calibration with seven memorized buffers (pH 1.68, 4.01, 6.86, 7.01, 9.18, 10.01, 12.45) and two custom buffers -Calibration time-out alarm -pH calibration using buffers with 0.001 resolution -pH readings with manual or automatic temperature compensation Up to 50 samples for log-on-demand -Two selectable alarm limits -Large easy-to-read LCD showing the pH or mV and temperature simultaneously, together with graphic symbols -HOLD feature to freeze the stable reading on the LCD -GLP feature to view last calibration data for pH and relative mV ranges