gtd audio 2x800 channel uhf diversity wireless hand-held microphone karaoke mic system 733 (2 hand held mics) gtdaudio gtd-audio g-733 wireless microphone system delivers superior sound quality and professional features. it is designed for a wide range professional application with 800 selectable channels, automatic frequency scanning, true diversity operation, tone lock squelch circuit, automatic transmitter setup. it's the perfect for professional use at any events.