Say goodbye to guesswork and instability the pH meter will bring you accurate and stable pH test results. With resolution of 0.01pH pH tester could fast to the testing and can test the PH value for any 0-16PH liquid.Digital pH meter small and light just like a pen. Portable water pH meter could be carried with you camping and swimming.Water is of life. PH meter identify high-quality water sources and bring you a . With a pH meter farewell to acid/alkaline water that is harmful to the skin and body.How to use the calibration solution: Wash the pH meter electrode with pure water (2-3 ) 1. Immerse the pH electrode in the mixed phosphate standard buffer solution with a pH value of 6.86 (at 25C) and shake it gently. 2. Use a small screwdriver to adjust the calibration potentiometer until the displayed value matches the pH value of the standard buffer solution at temperature.3. Clean the electrode with pure water first and then insert the electrode into the pH4.01 potassium hydrogen phosphate standard buffer solution for calibration. 4. After about two minutes. The displayed value should be within the error tolerance range compared with the pH value of the buffer solution.The so-called two-point calibration is to calibrate with two specifications of calibration fluids and the three-point calibration is to use three specifications of calibration fluids for calibration. Generally start calibration from 6.86. Then use 4.01.9.18Finished using. Clean the electrodes. Turn off the switch. Put on the protective case.Measuring range: 0.00-14.00PHAccuracy error: 0.01PHResolution: 0.01PHWorking temperature: 0-80Calibration : 2 3 points automatic calibrationElectrode: glass bulbTemperature compensation: ATC auto temperature compensationBattery: 2 x 1.5V (LR44 button battery)Color: blueMaterial: plasticPackage Contents:1 x PH MeterOnly the above package content other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.