Indoor Outdoor Digital Thermometer Hygrometer with 3 Wireless Sensors, 4.7 In...

As you know, too dry or too wet, too hot or too cold are both not good. Press the "CH" key to set the area (1, 2, 3 single flashing 5 seconds), and press it for 3 seconds to re-learn the current flashing guide, which can clear data of the current channel outdoor unit, and re-search the current channel for 3 minutes.

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