pH Buffer Solutions for Meter Accuracy Includes Levels of 4 and Higher

Press and hold the "CAL" button for 5 seconds. Rinse the electrode with clean water and dry. When the value starts to flash, press the "MODE/CAL" button (if the flashing value is greater than 222mV) or the "HOLD/TEMP" button (if the flashing value is less than 222mV).

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