Quick overview from the supplier:
Poly Blackwire 3225 Stereo USB-A Headset +3.5mm Plug (Bulk), Microphone noise-canceling, SoundGuard, DSP, Receive output from 20 Hz–20 kHz, Microphone 100 Hz–10 kHz, Call answer/ignore/end/hold, redial, mute, volume +/-, OEM, CABLE LENGTH 227cm
