Accurate Measurement: TDS Water Meter Can be Tested ppm, Electrical Conductivity, Celsius and Fahrenheit Temperature. Titanium Alloy Pobe, Large Back-Lit Screen for Easy Reading. Temperature Sensor Has Automatic Temperature Compensation. Please note: This meter CANNOT calibrate 4 Display Mode :TDS - ppm & C EC - s / cm & CTDS - ppm & FEC - s / cm & F. Auto Power Off & Data Hold Function: Automatic Shutdown after Two Minutes of No Opperation, so the Battery will Not Run Out. The Hold Button Makes Data Reading And Recording Easier. Press the Hold Button, and then Remove it from the Test Solution. Wide Application:The TDS Water Tester Can Be Used to Test Drinking Water, Fish Tank Water, Pool & Spa, Water Treatment and so on. Extra PH Test Paper:You Will Recieve-- 1 X Water Test Meter, 1 X Protective Leather Case, 1 X Ph Test Paper, 1 X User Manual.