The  Sony MDR-MDRXB950AP Extra Bass Headphones utilize 40mm dynamic dome drivers and special acoustical earcup enclosures to deliver an extended frequency response of 3 to 28,000 Hz with a sensitivity of 106 dB/mW.For extended comfort during long listening sessions, the earcups feature pressure-relieving cushions. They also fold for improved portability. A flat Y-type cable design helps prevent tangles and the included universal in-line smartphone remote control enables simple functions such as answering/ending calls and navigating media on your device. The SmartKey App is available from both the iTunes and Google Play store which allows for customization of the remote control.