①. Instructions for use of pH calibration powder: Calibration powder: pH standard solid. Can be used after adding water. Suitable for calibrating any type of pH meter. Each package can prepare 250ml standard solution. (Be sure to add water according to the required ratio, otherwise it will affect the calibration accuracy and increase the error) ②. Precautions: Please note that the pH pen probe is a glass product and is a fragile product. Please do not collide with objects. When the damage is irreparable, you must protect the probe. After use, use absorbent paper to gently absorb the water on the sample. ③. Requirements to pay attention to: The pH meter has been calibrated before delivery, the buyer does not need to re-calibrate after receiving the goods! In the following cases, the pH meter needs to be re-calibrated: 1. It has been used for a long time after calibration; 2. The special electrode is often used; 3. The measurement accuracy requirements are relatively high. ④. Battery installation: If the backlight brightness is greatly reduced or the display value is unclear, the battery needs to be replaced. When replacing the battery, simply pull out the battery compartment and replace it. Note: Battery polarity. ⑤. Ideal for preparing and drinking pure water, primary battery, boiler water, aquarium water, swimming pool water, photo rinsing, well water, deep water, laboratory, aquaculture, food processing, etc. A pH meter that can measure the pH value of each liquid. ⑥. With automatic temperature calibration: pH meter with automatic calibration button, automatic 2-point calibration, automatic standard solution detection, 5 seconds to complete calibration. For maximum comfort, simply remove the protective cap, immerse the pH meter electrode in the solution and measure with the push of a button. ⑦. Portable pH meter with LCD display: thanks to its compact size, you can easily take it with you. Just put it in any bag or bag to keep it neat and tidy in your bag. Large LCD display with good water resistance, so you can easily read the displayed value. ⑧. High accuracy: advanced electrodes equipped with sensitive sensors are in direct contact with the measured solution, fast and accurate, with a pH resolution of 0.01 pH and an accuracy of 0.01 pH. Measuring range: 0.00-14.00, operating temperature: 0-80 °C, automatic temperature calibration. ⑨. Portable: Small size, package weight only about 88 grams, but suitable for testing the pH value of drinking water, swimming pools, aquariums, RO systems, SPA or hydroponics. Don't worry about the effect of temperature changes on pH, the pH value automatically adjusts to the temperature.