Sonoff Smart Soil Moisture Sensor MS01:

• With MS01, you can detect soil moisture precisely and receive data on your mobile device. Soil moisture can be measured anywhere and at any time using MS01. suitable with both the Sonoff TH Origin and TH Elite smart switches.

Features:

• The watering system attached to the Sonoff TH16 or Sonoff TH Elite can automatically switch on or off (watering system not sold in the box) when the soil's moisture content exceeds the predetermined value.
• Google Assistant is compatible with MS01; you can ask it about humidity.
• Because the MS01 has an IP55 waterproof rating, you can water your flowers—even in the rain—without having to remove the sensor.
• Supports 90–250V AC input (TH16)
• TH16 - 3500W (15A) of power