3 in 1 reliably measure TDS, EC and temperature. Three different measurement requirements can be met by one metre.Equipped with a high quality titanium alloy probe, the TDS water quality tester allows a quick and convenient test. Suitable for drinking water testing, swimming pool, laboratory, plants, aquarium, well water, etc. water hardness tester with large backlit LCD. In addition, the red backlight (ppm number over 40) does not mean filtered drinking water (osmosis). Green backlight (ppm number below 40) shows TDS number qualified for filtered drinking water (notes: International standard accepted TDS number 40 as a separation line)Theppm meter allows button operation, turn it on and dip the TDS meter into water.water hardness meter is manufactured to particularly high standards and quality. Therefore, we have absolute confidence in our water test meter and will always be one of our products.