We had a shower where it appeared there could be a leak behind a wall, but how to know without cutting a hole in the wall? Well, my first try was to drill decent-sized hole in the wall, and insert an endoscope camera.I did this and it appeared it was dry inside the wall, so that was good news.But, if you had this meter, you can just push the probes through the wall and the meter will indicate if there is any moisture, a much less invasive measure. Actually, plumbers charged me $50 or so to do thSee full review