The Sonoff WTS01 is a waterproof temperature sensor designed to provide precise thermal monitoring for environments where moisture or liquids are present. Its sensing element is crafted from stainless steel, which is housed within a durable black ABS body measuring 50 x 6 x 6 mm, ensuring long-term reliability in demanding conditions. This wired probe can measure temperatures across a wide range from -55°C to 125°C and connects via an RJ9 (4P4C) connector at the end of its 1.5-meter cable. You can integrate this sensor with several Sonoff devices, including the TH16R3, TH20R3, TH16 Origin, TH16 Elite, TH20 Origin, and TH220 Elite models. For those who need to reach further distances, it is also compatible with the RL560 5-meter extension cable. These features make it a practical choice for monitoring water tanks, aquariums, pools, cooling rooms, or managing HVAC systems where accurate temperature data is essential.