I bought this room #thermometer two months ago. It works great, but the #battery already died! It just shows you how long this thing has been sitting in the Amazon warehouse. Plus, it wouldn't surprise me if the battery that came with it was a hunk of junk in the first place (2032 lithium 3 volt battery--or, least, it's *supposed* to be).
Luckily, I have extra since I have several devices that use this battery type.