The HC-SR04 is a popular and affordable ultrasonic ranging module that measures distance using high-frequency sound waves. Operating at 5V, it reliably detects objects from 2cm to 400cm with a resolution of approximately 3mm, making it ideal for navigation and automation applications.
This compact 4-pin module features a pair of round silver probe elements with protective mesh covers, an on-board crystal oscillator, and a clearly labeled PCB with VCC, Trig, Echo, and GND terminals for quick and easy wiring. It works seamlessly with Arduino, Raspberry Pi, and most other development boards and microcontrollers.