BOSE Quiet Comfort 20i Acoustic Noise Cancelling Headphones -Noise Cancelling -Inline mic/remote for iPod/iPhone music and call functions -Stay Hear + tips Soft, secure for hours of listening -Proprietary Technologies-bring music to life -Aware mode-use noise cancelling to shut out the world, or choose Aware mode to hear what's around you. -Control Module-Convenient on/off. Rechargeable lithium-ion battery.