Place them on a perfectly flat surface to compare readings and find that no two are the same, meaning they're virtually useless
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‘οΈ Continuous Temperature Monitoring with Relative Humidity Integration
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