One of the most interesting features of audio GSM bug transmitters is basically the ability to eavesdrop room sounds or voices from any distance without the use of a receiver. You only need to call the SIM number inserted in the device in order to activate it.
Said that we are going now to talk about the NANO-BUG, one of the latest spy GSM bug so much requested by many investigative agencies. This awesome voice activated GSM spy bug is a very sensitive, compact and easy to use audio transmitter equipped with internal rechargeable battery. Its size is only 31x31x10mm (naked) and can be used for remote listening to room or other places. Unlike many classic cheaper bugs, this professional spy tramsmitter uses a powerful DSP digital audio processor able to work independently to reduce noise or echo, as well as to control the microphone preamplification or other parameters improving listening in general.
Another interesting feature which also promises to be an excellent investment in terms of time is Voice Activation System (VAS). This latter feature allows the bug to call the number to be heard only when it is needed, that is when it detects sounds having acoustic levels above a certain threshold. Anyway this function can be activated or deactivated at will, by means of a simple SMS configuration command to the bug. Furthermore its knowles digital microphone, vey sensitive, can capture sounds even when audio source is 15 meters away from the bug!
Definitely NANO-BUG is a very respectable quad-band GSM bug, suitable to be used anywhere without distance limits.