Features: 1. Digital pH Meter Water Tester For those who need a home and laboratory pH tester, this pH meter is affordable and useful. 2. It's not just for home or laboratory use. It's not just for home or laboratory use. 3. Suitable for pH balance testing of drinking water, swimming pools, aquariums, food, etc. Specifications: 1. Measuring range : 0.00-14.00 pH 2. Precision : 0.01 pH 3. Power supply: button battery) (battery not included) How to measure pH: Step 1 - Remove the pH cover from the portable build meter. Rinse the electrode with distilled water and allow to dry. Step 2 - Press the On/Off button to turn on the device. Immerse the electrode in the solution of interest, ensuring that the entire electrode is submerged. Step 3 - Gently stir the solution and wait for the value to stabilize. The LCD screen will display the temperature and pH. Recalibration is necessary in the following cases: -Long periods of inactivity. - Used very frequently. -The accuracy requirement of the test is very high. - "cal" (calibration) was pressed and the electrode was exposed to air for a long time. Note: The data is all manual measurement, please allow 1-3cm error, due to the difference in light and display, there will be a certain color difference, depending on the physical object received Delivery quantity: (according to the main picture)