Fangrui Product Details Easy To Use, This Self-watering Diy Kit Is For Monitoring Soil Moisture Very Efficiently As It Automatically Wateres Your Plants And Flowers Automatic Irrigation System, Combines Pump, Pipe, Soil Moisture Sensor And 4-channel 5v Relay Module In One Plant Irrigation System, Including Kit For The Entire For Diy Drip Irrigation System A Capacitive Sensor, Which You Place In The Soil Around The Plant, And Through A Second And A Main Board, You Can Talk To The Plant. Do Your Plants Need To Rehydrate To See If They Are Dehydrated Of Your Plants, The System Can Automatically Water Your Plants. When Your Soil Gets Too Dry, The Pump Kicks In And Water Flows Into The Tubes And Pot. You Dont Have To Worry About Your Plants When You Go On Vacation Capacitive Soil Moisture Sensor: Working Voltage: 3.3~5.5vdc Output Voltage: 0~3.0vdc Interface: Ph2.54-3p Size: 98x2m (lxw) Pin: Analog Signal Output, Gnd, Vcc 1 Channel 5v Relay Module: Vcc: Connect To 5v Positive Power Supply Gnd: Connect To 5v Negative