This is the complete ActiveNoise set of our AN-RG-LN3 OUTDOOR device. Everything you need to get noise cancelling. To this box-shaped device, a directional microphone can be connected via USB. The microphone is pointed to the source of the noise. The device creates a reverse noise wave. Via two speakers, the reversed sound is send along the noise. (and cancels out the noises for the listeners up to 10 dB).