This is a DFRobot A02YYUW Waterproof Ultrasonic Sensor.

An ultrasonic distance sensor determines the distance to a target by measuring time lapses between the sending and receiving of the ultrasonic pulse. This is an easy-to-use commercial-grade ultrasonic sensor module of high performance and reliability, featuring a much smaller blind zone, wider sensing angle, and a certain penetration power(smog, dust) compared with other similar sensors

The ultrasonic sensor adopts a closed separated probe, waterproof and dustproof, which could be well suitable for harsh and moist measuring environments. All the signal processing units are integrated inside the module, so users can directly obtain the distance value through Asynchronous Serial Interface. With a 9600bit/s band rate, the sensor can easily communicate with the upper host or other MCU, which greatly shortens the developing cycle for users.

Connection Diagram:

Useful Link:

https://wiki.dfrobot.com/_A02YYUW_Waterproof_Ultrasonic_Sensor_SKU_SEN0311

Features:

1. High performance and reliability
2. Featuring a much smaller blind zone
3. Wider sensing angle

Package Includes:

1 x DFRobot A02YYUW Waterproof Ultrasonic Sensor