Allows you to adjust the level of noise cancellation on the new QuietComfort 35 wireless headphones II. All it takes is a push of the new Action button to take full advantage of the industry leading noise cancelling technology and completely block out the world around you, or let in some noise around you. You choose the level that best suits your environment. So go ahead, lose yourself in your music—or the quiet. Of course, QC35 headphones II also deliver the same performance and technologies you expect from Bose: volume optimised EQ so the sound is always true to your music, no matter the volume, and a noise rejecting dual mic system for clear calls, even in noisy environments. The built-in microphone also gives you easy access to your phone's default virtual assistant, like Siri. Just hold down the multi-function button and use the power of your voice to control your music and more. Plus, you'll be free from wires with Bluetooth and NFC pairing and voice prompts to walk you through every step of the process.