Ultrasonic Module HC-SR04 Distance Measuring Sensor for Arduino Highly cost-effective ultrasonic distance-measuring sensor that uses active sonar technology to determine distance.SpecificationsPower Supply : 5V DCQuiescent Current :Effective Angle:Ranging Distance : 2cm – 450 cm ~(1" - 17ft)Resolution : 0.3 cm ~(1/10" in) up to 2.5mPinoutVccTrigEchoGNDLibraryAvailable here: HRC-SR04 library