The QC20s are one of the first in-ear noise cancelling headphones from Bose. They give you more control over how you listen than ever before, in all kinds of environments. Block the outside world with full-on noise reduction and enjoy a more relaxing commute. Or, choose Aware mode and let some sound in – all while keeping your headphones on and your music alive with lifelike Bose sound. Absorbing, Noise Cancelling Sound With QC20 headphones you’ll enjoy lifelike, digital sound quality that stands out from the noise around you along with the freedom of an in-ear headphone. StayHear+ tips physically block some noise while Acoustic Noise Cancelling technology electronically reduces most of what’s left. It’s just you and your music, even in noisy situations. Furthermore, the TriPort technology and Active EQ combine to give your music a depth and balance that keep your daily soundtrack fresh and alive. The subtle details shine too. !– — Keep Alert With Aware Mode There are moments when you may not want to be so cut off from your surroundings. Crossing a city street for example or waiting for airport announcements. This is where Aware mode comes in. Instead of removing your headphones, just press a button and you’re back in touch with the sounds around you. Comfortable Fit StayHear+ tips create a soft, secure fit with no need to force them into your ears. The cone shape spreads contact evenly across the ear for maximum comfort, and forms a gentle seal that contributes to the headphones’ full-spectrum noise reduction. Functional Design Controls are all at your fingertips. Use the slider switch on the control module to turn noise cancelling on and off. The inline remote/microphone houses Aware mode and call answer/end buttons. And the 4-button remote offers control over the volume and music, plus access to voice-recognition apps such as Siri and Google search. Long Battery Life The built-in lithium-ion battery charges in just 2 hours with the included USB cable, and delivers up to 16 hours playing time per charge. A battery indicator light displays power status. And, even if the battery dies your music still plays. Carry Case Included When not in use, simply store your headphones and cables in the included carrying case.