Accuracy: ORP: ±5mV; PH: 0.05PH. Resolution: ORP: 1mV; PH: 0.01PH. 1 x ORP/PH Water Quality Detector. 1 x PH Pole Test Pen. Connect the PH and ORP electrodes respectively. 1 x ORP Pole Test Pen. After cleaning the electrode with distilled water or alcohol, wipe off the water on the plastic shell and shake off the small water droplets on the electrode to avoid influence.
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