Easy to use: The TDS reader freezes the measurement result when you press the "HOLD" button and automatically turns off after several minutes of non-use. PH meter has automatic calibration function and you can get the reading quickly Accurate and reliable: The resolution of PH is 0.01pH, accuracy 0.01pH. TDS measurement range 0 ~ 9999 ppm, Conductivity 0 ~ 9999 us / cm, accuracy 2%. ETDS 0 ~ 9999 ppm Automatic Temperature Compensation: ATC automatically accounts for temperature changes. Turn it on and insert it into liquid, read the display Wide Use: Ideal for home or laboratory use; Suitable for testing the pH balance of drinking water, swimming pool, aquarium, RO system, spa or hydroponics Easy to carry: Portable design and small size , it is convenient for you to carry