Rated 5 out of 5 by 4
Rated 5 out of 5 by 1m2n3b4v On my third one because they work
The best thing about this unit is that it will show you lower levels that aren't high enough to bring in alarm. That lets you know so that you can investigate the problem before just evacuating.
Rated 5 out of 5 by unusal1shopper Carbon Monoxide ALARM
I replaced an existing one with this,the manufacter gives them a 7 year usefull life I also bought that 1 at walmart.