Mono - USB Type a - wired - 20 Hz - 20 kHz - over-the-head - monaural - supra-aural - noise cancelling microphone The C3210 headset provides plenty of freedom with wired connectivity Listen to your tape recordings or use them when listening to telephone calls on Skype with these mono sound headset Hear low subs and soaring vocals with a frequency range of sound from 20 Hz-20 kHz