PSB M4U 2 Active Noise Cancelling Headphones featuring Room Feel. Around-the-ear design with closed, padded ear cups and adjustable headband and folds up for easier storage and portability. Active noise-canceling technology reduces distracting external sounds. Active listening mode uses built-in headphone amplifier for more powerful and precise audio with portable sources; Tri-mode operation allows passive listening (without batteries), active listening mode, and active listening mode with noise cancellation. In-line remote/microphone for hands-free use with iPod, iPhone, and iPad. In-line push-to-hear monitor control pauses the audio source and noise-canceling feature for brief conversations without removing headphones.