System Sensor 2151 This smoke detector is fairly rare. Brand System SensorModel 2151Manufacturer System SensorType Smoke Detector (Photoelectric, 4-wire)
Siemens ZH-MC-W Category : SiemensThe candelas selector on this alarm is broken, so the strobe is stuck on 75 candelas.
Notifier BNG-1 Category : NotifierThis pull actually opens with a “B” key, the key most commonly used by Simplex.
ADT ADT-PS Category : ADTPersonally, I think that the ADT logo on the head of this smoke is a bit ugly.