Review on Wireless Interconnected Combination Smoke and Carbon Monoxide Alarm with Voice Location - First Alert SCO501CN-3ST, Battery Operated by Raymond Vogel

I came home one day to find that a fire had broken out in the apartment below me. My house filled with black smoke. Panicked, I removed my animals when I called 911, initially assuming the batteries were dead since the house was empty about 4 hours before my return, and thinking nothing of it. When my insurance agent came to assess the damage I decided to test the detectors and they all charged! They just didn't shine. There were four in my house, one in each of the three bedrooms and another in my dining room where the smoke was thickest. They just didn't do anything when I needed them the most. At such an exorbitant price per unit, that's just absurd!