Quick overview from the supplier:
Headset A4tech FH100i, 40mm driver, 20-20kHz, 32 Ohm, 100db, 1.8m, 3.5mm(4-pin), Black
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Speaker Unit 40mm
Frequency Response 20 Hz - 20 KHz
Sensitivity 100 dB
Impedance 32 ohm
Microphone
Frequency Response 100 Hz-10 KHz
Sensitivity - 42 dB
Cables
Cable Length 180 cm
Port 4-Pin 3.5mm Plug