The ADP-2981 and ADP-2982 are wall mounted loudspeakers. The only difference between the two speakers is that the ADP-2981 has a strobe light annunciator. Both speakers have a port into which an FOI-2982 fiber optic isolator is inserted. Signals received by the FOI-2982 will drive an internal 8 watt amplifier to deliver sound on the 8 inch loudspeaker. Input and output jacks are also provided for cascading up to ten speakers for audio distribution.