System Sensor P4R Unlike my System Sensor P2R, this alarm does 4-wire operation. Brand System SensorModel P4RManufacturer System SensorType Alarm (Horn/Strobe)
National Time SG-C4HSZ Category : National TimeThis is a ceiling-mount Gentex Commander 4 Horn/Strobe, which is rebranded by National Time.
Honeywell 14506510-001 Category : HoneywellThe back of this LED looks identical to an older System Sensor mini-horn.