The unit sent broadcasting through the speakers
using the public address in premises broadcasting
It will return to the original automatic acoustic device functions
after end of public address broadcasting.
It is usefull to restroom , elivator etc.
Good designe , MP3 Player with 5W speaker and icluding ATT for D CLASS sound control.
Including sensitivity cintroller of PIP sensor and automatical switch
for can control the light with contact to sensor.