As they are used to test for peroxide and I have no other method of testing I cannot confirm they actually work properly. So when they work properly, they're really easy to use and come at a great price.
Efficiently Test Your Antifreeze And Battery Acid With A 3-In-1 Refractometer
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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
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TDS water quality tester - TDS water hardness meter (portable digital salt meter for water analysis)
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π¬οΈ Advanced 3-in-1 Indoor Air Quality Monitor with CO2/RH/Temp Data Logging and Audible Alarm - NDIR Sensor Technology
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π Dioxide Controller for Digital Gas Monitoring
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π Enhanced Precision with Backlit Professional Manometer for Differential Ventilation
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Digital multimeter RGK DM-12
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