The Plantronics .MCD100 , USB Desktop Speakerphone featuring 360-degree room coverage, Full duplex, conference quality audio, Plug-and-play USB connection (6' USB connection cord), Wideband audio for crystal clear sound, Clear UC and VoIP conference calls with no echo or cut-outs, integrated mute and volume controls, 3.5mm headphone jack so you can plug in a headset for privacy and Non-skid rubber bottom and feet