71 headset stereo pc headset usb headset design over ear type closed transmission modes wireless cable type of connection usb 20 radio range 12 m type of cable single sided operating time 16 h sound modes surround headset 71 software type of headphones headband features padded headband volume control led indicator onoff switch function mute sound system dolby headphone headphone transmission range 20 20000 hz sensitivity 107 dbmw head