Finally got around to testing the stud finder from the Place-That-Shall-Not-Be-Named*. Street price is $9.95. The instrument does an accurate job.
It finds studs, which is what you'd expect a stud-finder to do. It also finds METAL studs (or any metal) behind the wall. That is, it might do a fair job on pipes.
It finds, and traces, current carrying wires and will tell you, via a beep, if an electrical outlet is live.
All of these detections feature variable sensitivity.
And, just for grins, it includes a pretty bright LED light AND a 36" ruler (so you can measure over 16" (or 24") for the next stud!).
Beats the heck out of my 20-year old former unit, which mainly just guessed!
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- Not named because the mere mention of this company causes some to experience distress, palpitations, and excessive salivation.