Well, we got these when house was purchased prebuilt.Just setting this carbon monoxide and smoke alarm up we got the gist of what we'll hear in case we have any kind of issue in the house. One thing I do like is the "test" button. A simple tap will silence an annoying, unwanted announcement. I definitely appreciate the voice alerts though because there will be no second guessing as to why it is sounding an alarm. For example, it will let us know when carbon monoxide levels are too high. Batteries last so long and I always replace with recommend AA.