DuvinDD New Upgrade 15 Pack pH Calibration Solution 6.86/4.00/9.18-Box Packaging- Precisely and Easily Calibrated Your pH Meter/Pen/Tester pH Calibration Packets

The pH buffer solution powder is used to calibrate the accuracy of the electronic pH meter. The electronic ph meter has high accuracy, but after continuous use, it will become inaccurate. Therefore, the pH meter should be calibrated regularly. The ph meter may need to be recalibrated mainly in these cases: -Inactivity for long period, for example over 3-4 weeks. -Very frequently used. -Can't get a stable meter reading. -After testing strong acid/alkaline. -High test accuracy requirements. Directions for use: Step 1:Completely empty the powder into a dry glass container. Step 2:Add 250mL deionized water (or distilled water) to the beaker. Step 3:Stir until the powder has completely dissolved. Step 4:Put the pH meter in the solution and gently stir and wait a few seconds for the result. Tips: If you want the ph meter to have higher accuracy, you can use two or three solutions with different pH values for calibration at the same time. Generally, start calibration at 6.86 first, and then use 4.01 or 9.18. CAUTION: Not a drinkable solution! Specifications: Accuracy: ±0.01pH at 77°F(25°C) ? 5 packets of pH 4.00 Solution powder ? 5 packets of pH 6.86 Solution powder ? 5 packets of pH 9.18 Solution powder, cost-effective and flexible for using.