MS4 is an expander module for built-in mounting in the box of MAG8plus conventional fire alarm panel. The module provides 4 additional sounder outputs to the fire system.

Up to two MS4 expander modules can be mounted in the box of standard configuration of MAG8plus fire alarm panel thus providing 8 additional sounder circuits to the fire system.

Together with the PCB of the expander module are delivered also four 10K resistors and a transparent light pipe for LED indication.