HC-SR04 Ultrasonic Sonar Distance Sensor + 2 x 10K resistors Adafruit Industries Go to product viewer dialog for this item.
Submersible 1500W 28KHz SUS304 Industrial Portable Ultrasonic transducer Packs Go to product viewer dialog for this item. buy ultrasonic transducer
A reliable industrial transducer for precision cleaning available at Asonic . HC-SR04 Ultrasonic Sonar Distance Sensor + 2 x