Just found out I have to install a Carbon Monoxide Detector in my boat. I have had the boat for 32 years now without any kind of a CO problem. OK... Another piece of safety equipment.....Except.... What bugs me, is the things are bloody expensive and they are only good for a "fixed " period of time. There is an internal clock that is set when the unit is manufactured and shuts them down when the time is up. In other words, You can buy a 5 yr. or a 10 yr. unit and it may have been manufactured 2, or 3 years ago. You end up paying for something you don't get and for all of that time it may have sat in a warehouse some where.