Acoustic noise-canceling headphones Swivel ear pads fit any face contour Adjustable headband Compact storage For a variety of audio sources Noise-canceling headphones In-flight dual plug adaptor 6.3mm gold-plated stereo adaptor Users manual Two AAA batteries Travel leather bag The headphones use the superposition principle. An inverted version of the noise signal is created to cancel the noise. When two identical sound waves combine 180anddeg out of phase the result is destructive interference. It is the most effective way to cancel the noise from outside low-frequency sources.