... 3,page turner:page up/down 4,laser pointer,MP3 play 5,LCD diplay classroom wireless microphones for teacher This model microphone ... battery,signal link,volume and so on.6. Remote electronic laser pointer,page turner, USB upgrading.7. Pen designed,instead of ... Weight: 45G Dimension: 95.5*33.5*18(mm) classroom wireless hidden microphones for teacher audio/sound system