Bests & Worsts Reviews from Amazon

Bought this on 30March 2017, and just before the end of August it died. It began chirping like its battery needed replaced, so we put a fresh coppertop in it. It still was chirping. We stepped outside, to verify that it wasn't alerting us to CO levels. Battery out, battery in, another fresh battery, a third new battery - nothing made any difference. We finally just removed the battery. Apparently, it's the End Of Life death knell for its 7-year life expectancy. Mine has a mfr date of "2016 Jun 07" stamped in it.