The RYOBI LED Whole Stud Detector is a great product for detecting whole studs behind your wall. The multi LED’s allows you to see the entire stud and not just an edge or center. It uses Auto Deep Scan, technology designed to determine the thickness of your drywall so you can accurately assess what is behind it. With its material detection capabilities, you will always know when you are over metals (non-ferrous), wood, and AC wire.