Model: PH-02 Measuring range: 0-14ph Accuracy: 0.01ph Error: +0.1ph Probe: Glass probe Battery: 3V (CR2032 button battery*1) Operating temperature: 0-50C Size: 155*31*18mm Weight: 50g Model: TDS-A1 Measuring range: 0-9990ppm or -9990us/cm Temperature measuring range: 0.1-80C 32.0-176.0F Accuracy: 1ppm 1us/cm Battery: 3V (LR44 button battery*2) Probe: Alloy probe Size: 155*14*30mm Net weight: 55g Water pH Meter Kit: A very complete kit for checking the pH of purified, drinking, tap, faucet, recycled, beverage, or swimming pool water. It can also be used to test aquarium water and the water we use for hydroponics, aquaculture, and food processing. Easy-to-use pool pH tester: You don't need any tools, just dip the pH meter electrode into the solution. Press "ON/OFF" to turn on the electronic pH meter and shake gently for a few seconds until the reading stabilizes. These 2-in-1 pH and TDS meters are also ideal for home or laboratory testing. The pH tester is easy to calibrate: TDS pens are self-calibrating and can be used directly, PH pens need to be calibrated, so there are several sachets for different PH powders in the package. The pH tester self-calibrates at three points. Accurate digital display electronic pool pH tester: Use the digital display to get the accuracy number instead of comparing the color with the pH test paper, to avoid accuracy caused by different light, and it is also useful for people with darker skin tones. Comes in a package containing 2 in 1: one to measure the pH of the water and the other to measure the rate at which solid particles dissolve in water. The TDS/PH tester is small and light, just like a pen.Good quality product