Specifications: unpackaged product dimensions: 230x200x100mm Speaker Diameter: 50mm Frequency Range: 20-20KHz Sensitivity: 115dB±3dB Impedance: 21Ω±15% Microphone Diameter: 6mmX5mm Microphone Sensitivity: -44±3dB Microphone Impedance: 2.2KΩ Working Current: ≤100mA Input Plug: 1 Jack USB