"Convenient test methods: This water quality test pen is easy to use and very convenient to detect water quality, which is very suitable for family use. Avoid interference: This water quality test pen uses an alloy probe to avoid interference from the magnetic field of water to the greatest extent, which makes it more accurate, and can quickly display the value of the test during the test. Detect impurities: TDS tester can detect some elements of impurities in water, such as soluble salts, ionic organic compounds, heavy metal ions, etc. ., which provides great convenience for you and your family to get cleaner water. Easy to use: The measuring principle of the TDS meter is to measure the conductivity of water, which indirectly reflects the TDS value.If you want to use it, just put the TDS test pen into the water to be tested and pressing the switch, the display will immediately show the TDS value of the water. Very easy to use. Widely used: It can be used in aquariums, beverages, quality control, fish farms, food processing, laboratories, schools, universities , swimming pools, etc. Description: Our water quality test pen embodies high accuracy, not easy to corrosion and quick response, can avoid interference from the magnetic field in the water, and display the TDS value of the water in time to reduce the error. Features: Name: Water Quality Test Pen Material: ABS. Dimensions: approx. 15 x 1.7 cm. Weight: about 20g. Package: 1 water quality test pen. (Only the above package contents, other products are not included). Notes: 1. Due to the camera, light and display screen difference, the item's color may be slightly different from the picture. 2. Due to manual measurement, the sizes shown may vary by 0.1-2cm."