Heat Thermometers

Gads, the spelling doesn`t look right.hmmm. Well, now that I have a new baffle in my PE insert (1985) I am thinking about getting a thermonitor to check periodically the temp of the fireplace. Don`t know a damn thing about them, cept that some people on this forum reccommend them. Well, this dumber than dumber question is where do I put it? Right in the fireplace or what? Clearly there is no stovepipe to attach it to, so where does it go? Please bear with me here folks,even though I have been burning wood for a number of years, since joining this forum, I have discovered how lilttle I know. Also, what is the cost of one of these things? Worthwhile investment or not?

Thermometer" yes thanks uncle Rich.. worthwhile or not, and where does it go in an insert??

begreen: do you mean right inside the firebox? I mean do these things take that kind of heat? I take it that they are not magnetic? Just thought that now I might need one cause since installing the baffle, the glass is much cleaner, meaning more heat for sure is directed towards the front of the fireplace. Can`t thank you guys enough for telling me that if the fireplace came with a baffle "replace it". Right on!!