content: this product is the obsolute worst and it took me six years to discover this. we bought our house brand new and it was already equipped with this smoke alarm system. when the chirping started about several months ago we didn't have a clue (and still don't) on how to stop it. there was no manual or instruction left. its electric and I don't know how to get to the battery. i can't believe they put these smoke alarms in new houses without a manual. after viewing all the negative reviews and seeing that the product is discontinued, we will probably have to replace all of smoke alarms in our house. there's one in every room. how can a company provide a product with no instrutions to service it.