Blumat Maxi Sensors - 2 Pack Automatic Smart Watering - INCREASE Yields Senses Soil Conditions, Turns Water On and Off No Batteries, No Timers.. and Just the Right Amount of Water For Larger Pots and Bigger Plants than the Regular Tropf Blumat Each Maxi Sensor Comes with a 8mm x 3mm x 8mm Connector Tee