ORP: ± 999mv. TDS function gives you a clearer understanding of the concentration of impurities in water. TDS: 0-999ppm, 1000- 9990ppt. TDS: 1ppm, 10ppm. TDS: ± 2% F.S. Temperature can affect reading levels, digital pH tester has an even better range of 0.1 ° C-60.0 ° C (32.0 ° F-140.0 ° F), automatic temperature compensation can ensure that you are getting the best reading.
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