1、TDS meter measuring principle is to measure the electrical conductivity of water and indirectly reflects the TDS value 2、Test the impurities in water such as some elements of soluble salts, ionic organic compound, heavy metal ion, etc, offering much convenience for you and your families to get a more clean water 3、It supports hold function that can save measurement results for easy reading and record 4、Automatic power-off function allows it to power off after 5 minutes without any operation in order to save power 5、The TDS meter can be widely used for aquarium, beverages, quality control, fish hatcheries, food processing, laboratory, schools, colleges, swimming pools, etc Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Sold by-YJL official store