Gain Express Digital Waterproof 0.00~14.00pH pH & Temperature Meter with Backlight/Replaceable Electrode, 0.01 Resolution +/- 0.1pH High Accuracy, for Pool, Aquarium, Hydroponic LCD indicates and display both pH and temperature Replaceable pH Electrode and IP65 rproof protection level With auto-buffer solution recognition Has Automatic Temperature Compensation (ATC) and 3 Point Calibration With CE RoHS Marking, passed & comply with all the necessary health and safety required standards set by the European Directives