We knew better, but, bought fire and smoke alarms from a door to door sales woman. Less than 1 week, we had a kitchen fire. The $10 alarms sounded fast, the new high priced alarms never sound. When I called to complain, was told that the new alarm had to have big particle of smoke to sound, the cheap one would sound on any particals. I asked the sale woman, have never heard from store owner or adjuster, to pick up the useless alarms and refund my money. She gave me a song and dance about the alarms had to have direct smoke, a burning napkin blew out, held within 2 inches of new alarm. It did sound off. So, if I have a fire that will burn down our home, and people inside, the alarms will sound off as soon as the burning napkin directly reaches this new alarm. I do not feel safe with this over priced, useless, fire alarm. I was told this new fire alarm was made in the USA, I cannot find just where this was made or by what company. Do your research, never buy this unsafe useless product. It is a scam, with no recourse. One example used was a 9 volt battery would burn steel wool. I disagreed. Steel wool will not burn. Brillo pad made of steel wool and soap will burn. Soap will burn.