#Widely Use:# TDS Water quality test pen used to test the water TDS value, water conductivity, in order to judge the degree of pure water, and the environment is the function of temperature, products can be widely applied to water treatment industry, drinking water, individual staycation, field operation as water quality inspection tool. # Protect Your Health:# The water that flows from our taps is full of chemicals, pollutants and metals. Well, the only way to make sure your water is clean and healthy is to test it regularly. With this TDS tester, you can check any time on your water filtration, ensuring that you and your family won't be exposed to unhygienic drinking water. # Features:# Lock function: Makes it easy to read and record, press HOLD button then remove from test solution. 4 Display modes: Press SHIFT button: TDS - ppm & C, EC - s/cm & C, TDS - ppm & F, EC - s/cm & F. 9 minute Auto Shut Off feature, so battery won't run down. Measurement Range: Conductivity: 0 - 9990 s/cm TDS: 0 - 9990 ppm (parts per million) Degrees Celsius: 0.1 - 80.0C, Fahrenheit: 32.0 - 176.0F. Accuracy: 2%. Net weight: 1.94oz (55g) Size: 6 x 1.2 x 0.6 inches (154 x 30 x 14 mm) # How to use:# STEP 1:Remove the electrode protective cap before use STEP 2:Press the ON/OFF button, and immerse the meter into the solution. (The solution should not over the immersion line) STEP 3: After the numerical display is steady, press the HOLD button and take it out of the solution for checking the result STEP 4: Wipe clean the electrode after using, turn off the meter and replace the protective cap # Parameter:# Electric conductivity (EC) : 0”9990us/cm. Total Dissolved Solids (TDS) : 0”9990ppm. Temperature : 0.1”80.0ƒ 32.0”17.