Calculated Industries Blind Mark Magnetic Drywall Electrical Box Locating Tool (3-Piece)

The Blind Mark helps you get perfect drywall cutouts without measuring. Simply insert targets into outlet boxes before hanging drywall. After installing the drywall, slide the Blind Mark locator over the area where you think the receptacle is located. When you pass the locator over the outlet box, the locator will snap precisely into place where the target is located in the box. Trace around the locator, cut, then install. With the Blind Mark you simply put it up once, cut the hole and you're done.