Equipped with 201T-F 3-in-1 Combination pH Electrode, Auto Temp. Compensation, measuring pH and temperature simultaneously AdvancedAuto Calibration Mode with Calibration Guide and Self-Diagnosis Advanced digital processing technology helps generate quick and stable pH readings IP54 Spill-proof and Dust-proof, durable and reliable Comes with easy-to-install electrode holder and pre-mixed calibration solutions 50 Groups of Data Storage