Sony MDR-ZX770BT/L Bluetooth Wireless Stereo Headphones w/Microphone NFC - Blue (Certified Refurbished) Enjoy a tangle-free listening experience thanks to high-quality Bluetooth audio streaming with AAC and apt-support.Easily connect to your devices. Access all of your favorite streaming services from your smart device to your headphones in a single touch with Near Field Communication (NFC).Hands-free calling. A built-in microphone makes hands-free phone calls a breeze. Once your phone is paired, simply press the phone button on the earpiece to accept incoming calls, and press it again to end the conversation.Up to 17 hours of music on a single charge. To connect with BLUETOOTH device: 1.Place the BLUETOOTH device within 1 m (3 feet) of this unit. 2 Enter pairing mode on this unit. Press and hold the POWER button for 7 secs. Indicator flashes blue and red after you release the button. 3 Pair the BLUETOOTH device to detect this unit. Select "MDR-ZX770BT." Enter passcode "0000" on BLUETOOTH device. 4 Make the BLUETOOTH connection from the BLUETOOTH device.