GE 521BXT Category : GE I think that this smoke detector might be intended for use in security systems.
Cerberus Pyrotronics EH-24S Category : Cerberus PyrotronicsThis unit is missing the large capacitor off of its circuit board.
Gamewell M46-28 Category : GamewellThe key reset cover is an additional device that the pull station is mounted on.
Pyrotronics ES0-24S Category : Cerberus Pyrotronics, PyrotronicsThis is a rebranded Wheelock horn/strobe, and a pretty rare one at that since it has an electronic horn mechanism...