My friend has a EACH G200 a really cheap headset here are the specifications:
Driver diameter: 50mm
Impedance: 32Ohm
Sensitivity: 114dB +/- 3dB
Frequency range: 20-20KHz
Mic dimension: 6.0 * 5.0mm
Mic sensitivity: -34dB +/- 3dB
Mic impedance: 2.2kohm
Directivity: Omnidirectional
And I have...