The probe can be inserted directly into the soil. It is a digital display of soil moisture. When the humidity is below the set value starting pump starts watering, when humidity reaches the set value to stop watering. The operation is very simple. It is intelligent humanization. Parameters:Product name:Soil Moisture Controller Module Model:XH - M214 Power supply voltage:DC 12 V Output way:Output switch Humidity range:20-99% RH Control precision:1% RH Control current:10 A Net weight:About 28 g Size:52 * 43 * 16 mm Using attention:Please follow the wiring diagram of the description. You can choose the appropriate wiring mode according to the load voltage you use 1>. F0 setting start humidity(the humidity of the solenoid valve or the pump start working) Pre the SET button to display F0 and pre the SET button to display the start humidity, and pre +/ button to SET the humidity value 2>. F1 setting stop humidity (the humidity of the solenoid valve or the pump stops working) Pre +/- button to switch to F1, pre the SET button to display the stop humidity value, and pre +/ button to SET the humidity value 3>. F2 humidity correction Normal use without correction error.The correction of values in the use of multiple modules at the same time is conducive to a unified management operation. Note:Item color displayed in photos may be showing slightly different on your computer monitor since monitors are not calibrated same. Please allow 1-3mm slight deviation due to manual measurement. Thank you! Package include:1pc Digital Humidity Controller