Review on 🔍 Allprettyall 5-in-1 Stud Finder Wall Scanner with LCD Display & Auto Calibration: Detect Wood, AC Wire, Metal Studs, and Beams with Sound Warning by Chris Kirby

This mandrel finder seems to be quite reliable, but calibration after turning on the device is very important. Make sure the unit is flush with a spot on the wall where you know there are no bolts or wires underneath. I have used my small neodymium magnet spike finder in combination with this device and found the spike very accurately every time. The device can sometimes get tangled, so it's important to move slowly along the wall, giving it time to "lock in" and beep on the hairpin.