The BG-EXM-SM5 is an extension microphone for the BG-SMB-5M speakerphone. It features 360° of audio pickup and extends the pickup range for the speakerphone up to 33 feet. Each expansion microphone is equipped with a mute button and green/red status led indicator for easy on/off control and plugs directly into the RJ11 ports on the BG-SMB-5M.