Features: The test pen with digital display screen, with data and convenient reading. Simply place the TDS detection pen in the water to be test, press the button, and the display screen will immediately display the TDS values of the water, allowing you to have a more understanding of the purity of the water and convenient operation. The detection pen shells adopt plasticmaterial, and the probes adopt metal alloy, which is not easily damaged and has high sensitivity. Three types of impurities can be measured in water quality. on business/play/shopping, detect the TDS values of water, with a measurement accuracy of 2%. The factors that affect the TDS values test include high water temperature, large water bodies, and high pollution concentrations. Specifications: Material:ABS Size:Approx.150x16mm/5.9''x0.6'' Usage 1. Open the TDS pen cover. 2. Presses ON-OFF button and the display screen will light. 3. After the reading stabilizes, record the values. After the test is completed, turn off power and wipe the TDS pen probes clean with dry paper. Note: Please allow 1mm errors due to manual measurement. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package includes: 1x TDS Meter