Bests & Worsts Reviews from Amazon

Please read and take note ... look at the manufacture date on them when you get it. I should of read the reviews in detail. Bought a 3 pack, one of them started beeping (5 chirps-end of life) 1 month after installing it, and also after return period. I looked at the manufacture date and it is from Nov 2010. I will throw them all out, nothing worse than this happening in middle of the night. So PLEASE check them before your return period ends. David