Sony ZX  MDR-ZX310AP/L Series Headband Stereo Headset Folding mechanism of its own that can be compact size Quick folding mechanism adopted simple, easy to carry.Connectivity Technology: Wired Model: Dynamic Sealed Driver diameter: 30mm Playback frequency: 10 ~ 24000Hz Impedance: 24 Output sound pressure level (sensitivity): 98dB Plug: 3.5mm stereo mini plug