Review on Enhanced 5 in 1 Stud Finder Wall Scanner - Ultimate Wood Beam, Drywall, Joist, Pipe, AC Wire and Metal Studs Locator with LCD Display - Best Electronic Wall Detector for Precise Edge and Center Finding by Kent Kings

Amazing product, especially for the price. The included battery was fully charged and easy to install. The instructions are very detailed. A bit awkward in some places due to poor translation. For example, he insists on the importance of calibration but does not say HOW to calibrate. So, I'll tell you: 1. Press the power. (All buttons require short clicks only. Do not hold them down.) 2. Press the mode button until the desired option appears on the screen.3. Hold the scanner firmly against the wall (helps if you start in a spot where you are sure there is NO stud).4. The scanner is being calibrated. Just hold it still until the battery icon disappears. 4.b. If calibration is not automatic, press the button on the left side of the scanner. Just a quick click and the battery icon should disappear.5. Slowly slide down the wall, keeping firm but gentle pressure. Obviously humidity can affect these scanners so it is best to work below 60%. Hope this helps you!