HC-SR04 Ultrasonic Distance Sensor Module (2–400 cm)

Low-cost ultrasonic distance sensor using 40 kHz pulses to measure distance. Provides TRIG and ECHO pins for simple microcontroller interfacing — ideal for robotics, obstacle avoidance, and level sensing.

• Range: approx. 2 cm – 400 cm
• Supply voltage: 5V (logic considerations for 3.3V MCUs)
• Interface: Trigger (input) & Echo (output)
• Widely used in hobby robotics and automation