- Power Supply: 5V DC
- Ultrasonic Frequency: 40Hz
- Resolution: 3mm
- Measure Angle: 15°
- Ranging Distance: 2cm - 4m
The HC-SR04 Ultrasonic Range Finder is an economical sensor that provides 2 cm to 400cm of non-contact measurement functionality with a ranging accuracy that can reach up to 3mm. Each HC-SR04 module includes an ultrasonic transmitter, a receiver and a control circuit.

There are only four pins that you need to worry about on the HC-SR04: VCC (Power), Trig (Trigger), Echo (Receive), and GND (Ground). You will find this sensor very easy to set up and to use for your next range-finding project!