Headphone spec Driver unit: 50mm dia.dome Impedance: 32 Frequency: 20Hz~ 20KHz Sensitivity: 105dB+ 3dB Max. Input: 100mW Length of wire: 250cm+ 5cm Microphone spec Directivity: Omni Impedance: 2.2K Frequency: 20Hz~ 20KHz Sensitivity: -58dB+ 3dB Operating voltage: 4.5V Control Mute/ Volume up/ Volume down