SMS Audio STREET by 50 Wired Over-Ear Active Noise Cancelling Headphones - Black Active Noise Cancelling: Advanced active noise reduction technology effectively reduces distracting low frequency background noise while preserving characteristics of audio source at the press of a button, makes you focus on what you want to hear, enjoy your music, movies and videos. The noise cancellation function can work well both in wire and wireless mode. Active Noise Cancelling: Advanced active noise reduction technology effectively reduces distracting low frequency background noise while preserving characteristics of audio source at the press of a button, makes you focus on what you want to hear, enjoy your music, movies and videos. The noise cancellation function can work well both in wire and wireless mode. Active Noise Cancelling: Advanced active noise reduction technology effectively reduces distracting low frequency background noise while preserving characteristics of audio source at the press of a button, makes you focus on what you want to hear, enjoy your music, movies and videos. The noise cancellation function can work well both in wire and wireless mode. Active Noise Cancelling: Advanced active noise reduction technology effectively reduces distracting low frequency background noise while preserving characteristics of audio source at the press of a button, makes you focus on what you want to hear, enjoy your music, movies and videos. The noise cancellation function can work well both in wire and wireless mode. Never Power OffThe wireless mode: A built-in 360 mAh battery provides up to 20 hrs of continuous playback per charge. The Wired mode: you can also connect it to your device by the included audio cable. Thus it will never power off.