Mst-100b stands for unit

·LED indicates speech mode, working status, low voltage indication and other content information.

· The external communication antenna 

· The microphone has a light ring to display the speech status.

· Power Supply: DC 4.5V, AA1.5V*3

· Transmitted power :10mW

· Frequency offset: ±45KHz

· Microphone head: capacitive, single pointing

· Sensitivity :-47±2dB@1KHz

· Frequency response: 30-18khz