Review on 🔋 2-Pack Battery Operated FIRST ALERT CO400 Carbon Monoxide Detector - No Outlet Required by Dave Butler

I would give good ratings because it's easy to use and I think it will work properly, but after only having it for a few months one device already started the ERR code to beep. This code means the end of life. It is written on the blocks that they have a service life of 7 years once they have been used. Well 2 months is a far cry from 7 years but I checked the date of manufacture and it was manufactured in October 2006 which is why Revain sells 10 year old detectors. and apparently the date of manufacture plays a role and not just the start of use.