Review on Enhance Detection Accuracy with Klein Tools ET140 Non Destructive Detection by Troy Hamilton

I don't recall reading anything about the product that says it's suitable for plaster on walls, but there are many false positives. I had a small leak in my roof and wanted to understand how serious it was so I was hoping this would help. He barely seemed to notice the dry patch of plaster compared to feeling a little more damp in an area that was clearly slightly damp (a small patch of water was visible where it was wet). However, the humidity seems to be too high at any setting compared to what is actually in the wall. Regardless, in some places it appears as if the humidity is 100% (where the reader just beeps the whole time), but there's literally no sign of water at all (i.e. there weren't any leaks near that area). In short, easy to use, just don't think you can trust what it tells you.