System Sensor MA/SS-24D Just another duplicate. Brand System SensorModel MA/SS-24DManufacturer System SensorType Alarm (Sounder/Strobe)
FCI S241575-FC Category : FCIUnlike my other FCI-rebranded System Sensor SpectrAlert Classic, this one does not have an FCI logo on the front.
Wheelock AES-DL1-WS-24 Category : WheelockDepending on which set of inputs has power applied to it, the alarm will produce a different tone.