Full duplex microphone / audio bridge systems that deliver a good quality of sound, it is ideal for small group or individual. It is a plug and play with a standard USB microphone. The microphone is designed to deliver and ideally pick up within a range of 120 degree as the unit faces you. Echo cancellation technology allows the speaker put it right beside the device without any echo. USB and analog mix features allow cell phones users to join the MCS conference without having a PC or internet connection. Just a simple 2.5 mm stereo mini jet cable connects to the cell phone and the remote cell phone users can join the MCS conference.