designer's own words:The horn sound of vehicle on the road is a noise to others. Through this klaxon drivers will deliver the sound to a particular target and will not make unnecessary noise to the surroundings. In order to deliver horn sound easily and quickly to a particular direction operation mechanism of joystick was used. Like ordinary klaxon, if you press the center the sound is spread to all directions. If you push the horn to a particular direction, the sound is emitted to the pushed direction. After audio signal is altered it is loaded on the ultrasonic wave signal so it has characteristic of super directivity. Therefore, the sound is emitted like light and it can be shot aiming at particular region and it is designed so that if it is out of aimed region it cannot be heard.