Note: If you are going to place the sensor to very humid soil, that would make it very easy to get the sensor surface erosion within several days, hence we suggest to use this one Analog Capacitive Soil Moisture Sensor- Corrosion Resistant instead.
SPECIFICATION Power supply: 3.3v or 5v Output voltage signal: 0~4.2v Current: 35mA Pin definition: Analog output(Blue wire) GND(Black wire) Power(Red wire) Size: 60x20x5mm(2.36x0.79x0.2") Surface finish:Immersion Gold
SHIPPING LIST Moisture sensor x1 Analog Sensor Cable x1
Wiki : https://www.dfrobot.com/wiki/index.php/Moisture_Sensor_(SKU:SEN0114)