[Note] There are 3 packages of PH calibration powder in the package. The first time you use it, you need to summon it If you don't use it for a long time, you need to clean it again.[Sensitive electrode] The pH tester has a sensitive electrode sensor that can read accurate pH levels. Accuracy range: +/- 0.01: can test the PH value of any 0-14PH liquid.It is recommended to use single-point calibration 4.01 in acidic environment for a long time, neutral single-point calibration 6.86, and alkaline single-point calibration 9.18High-definition screen, backlit display, can handle freely in the darkPH measurement range: 0.00~14.00Error: +/- 0.1Accuracy: 0.01PHTemperature compensation: 0~70Power supply: 3V button batteryScreen display: high-definition backlightWorking environment temperature: 0~50Size: 150 x 31 x 12mmWeight: 110gColour: yellowMaterial: plasticPackage Contents:1 x Yellow PH test pen3 x PH calibration powder1 x English manualOnly the above package content, other products are not included.Note: Light 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.