Bests & Worsts Reviews from Amazon

I did not test these alarms, but the instructions tell me that when you depress the test button, it not only checks that the alarm is working, and that the battery is good, but it also checks that the smoke/fire and carbon monoxide detector is actually working! This is important, since the old style alarm only confirmed that the alarm itself was making NOISE, and that the battery was OK, it did NOT tell you that the detection function is working correctly. NO MORE HAVING TO LIGHT A CANDLE OR A MATCH TO TELL IF YOUR ALARM IS REALLY WORKING OR NOT. Now this is very important for your peace of mind that you know alarm is actually working as it should. One more fact. This alarm detects fire/smoke with a PHOTOELECTRIC detector............these are much faster and more dependable than the old ionization types. If you buy any new alarm, but sure to buy one that works on the photoelectric technology rather than the ionization technology. They cost about the same.