WTV-S1 PIR Sensor Sound Module Built-in amplifier, can drive 0.5W ... of the general audio output power 7.Audio playback with good quality 8.Can update the voice many times, ... .Adjustable volume, can be used in various environments12.Matched with the simple PC software which is powerful, easy to operate ... for advertising announcers, banks , hospitals , gradens , and etc. PIR Sensor Sound Module