This is a 1 Meter Long Waterproof, sealed, and pre-wired digital temperature sensor probe based on a DS18B20 sensor. It is very handy when you need to measure something far away, or in wet conditions. Because they are digital, you don’t get any signal degradation even over long distances.
These 1-wire digital temperature sensors are fairly precise (±0.5°C over much of the range) and can give up to 12 bits of precision from the onboard digital-to-analog converter. They work great with any microcontroller using a single digital pin, and you can even connect multiple ones to the same pin, each one has a unique 64-bit ID burned in at the factory to differentiate them. Usable with 3.0-5.0V systems.
The only downside is they use the Dallas 1-Wire protocol, which is somewhat complex and requires a bunch of code to parse out the communication. When using a microcontroller put a 4.7k resistor to the sensing pin, which is required as a pullup from the DATA to the VCC line.