Features:Easy to Use: Simply immerse the pH meter electrode in the solution to be tested, readings are quickly display on a large lcd displayWide Application: Ideal instrument for any aquarium, the fishing industry, swimming pools, spa, school laboratories, food & beverage, drinking water etc.Auto Calibrated:Features in-built calibration with 2 buffer powders.Just press a button to finish the calibration. This pH meter is factory calibrated. Users can use it directly.Fast and Accurate Results: No need to work with those annoying color charts and test strips. Resolution: 0.01 pH, Accuracy: 0.01 pHCompact Portable Design: Pocket fitting pH meter that's also lightweight and compact. Total concealed fit in your bag or pocket for easy, casual carrying.Specification:Display: LCD DigitalAccuracy: 0.01Resolution: 0.01Operating Temperature: 0~60CMeasuring Range: 0.00~14.00Probe Type: Precision glass bulb electrodePower Supply: 2*1.5V LR44 Batteries(Not included )illustrate:Step 1.Remove protective cap.Step 2.First rinse the electrode with distilled water and suck it with filter paper.Step 3. Turn the meter on by pressing ON/OFF key.Step 4. Immerse the pH meter electrode in the solution to be tested (should not be over the immersion line).Step 5.Stir gently and wait around 30 seconds till the reading stabilizes.Step 6.After finishing, clear the electrode with pure water, turn the meter off by pressing ON/OFF key.Step 7.Always replace the protective cap after use.Instructions:1.Turn on PH meter2.Disolve each buffer solution in 250ML of distilled water3.Immerse the electrode into the PH 6.86 solution,(under the temperature of 25)4.Press the CAL(calibration)button for 5 seconds and release-Display will start flashing 6.86-Wait until the display stops flashing.Rinse the electrode with distilled water and dry it with filter paper.5. Immerse the electrode in PH 4.00 solution,-Press "CAL" button for 5 seconds, then press and release immediately second time-Reading will start flashing 4.00-Wait until display stops flashingRinse and dry the electrode with distilled water as before.6.Place the meter back to the buffer solution to test calibration. If incorrect, please repeat the calibration7.If approximate PH of your test solution is known to be above 7.0,calibrate the meter using 6.86 and 9.18 solution. To do this,please follow the calibration chart,The third step is the calibration method for 9.18 point.Package includes:PH detection pen*1 Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.