The Sonoff MS01 is a smart soil moisture sensor designed to help you keep a close eye on the hydration levels of your plants. It uses a capacitive sensing method to measure moisture within a range of 0 to 100%RH, which allows it to provide accurate readings without the rapid corrosion often found in other sensor types. This device is built to be durable, featuring a plastic housing with a V0 flame retardant rating and an IP55 waterproof level that protects it from dust and splashing water during regular garden or indoor use. Connecting the sensor is straightforward via its RJ9 connector and 50 cm cable, though you can extend this reach up to 10 meters if you use an RL560 extension cable. It is specifically designed to work with the TH Elite, TH Origin, TH10, and TH16 series of switches, enabling you to automate your irrigation systems. Because it integrates with these switches, you can also manage your plant care through Google Assistant. Weighing only 28 to 50 grams and measuring 130 x 30 x 13 mm, it fits discreetly into the soil without disturbing the root system, operating reliably in temperatures between 0 and 60°C.