The MDR-ZX220BT headphones are perfect for everyday use the swivel folding design makes travel easy and can store away neatly when not in use and you can Listen longer thanks to 8 hours of Wireless playback thanks to the built in Li-ion battery. Hear the smallest of detail in your music with the 30mm dome drivers tiny &lightweight the drivers deliver dynamic sound and quality audio. The built in microphone means you can answer your calls even when your phone is in your pocket or bag listen to your music for longer - the MDR-ZX220BT can give you up to 8 hours of wireless playback when fully charged.