
I bought two of these for a couple of my technicians to check hydronic boiler systems anti-freeze levels. So far so good!

TDS water quality tester - TDS water hardness meter (portable digital salt meter for water analysis)
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Digital PH Meter Tester - Tiaoyeer Water Quality Tester With ATC, 0.01PH High Accuracy, 0.00-14.00 Measurement Range, 0.01 Resolution For Drinking Water, Aquarium, Swimming Pools, Hydroponic
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π― Honey Refractometer with Automatic Temperature Compensation (ATC) - Tiaoyeer Moisture, Brix, and Baume Refractometer for Honey, 58-90% Brix Scale Range - Honey Moisture Tester
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Portable digital multimeter with sound continuity and thermocouple (electric tester) LTX DT-838
7 Review