Digital Electric PH/TDS/EC Conductivity Meter Tester Hydroponics Water Test Pen
4 Display modes: press SHIFT button: TDS - ppm & °C, EC - μs/cm & °C, TDS - ppm & °F, EC - μs/cm & °F. TDS&EC ( WHITE OR BLUE). First, rinse the electrode with distilled water and suck it with filter paper.