Check the listing for details. Calculated Industries 7310 StudMark Magnetic Stud Finder with Removable Markers. Condition: New. Listed at 14.95 USD. This item is Brand New in Perfect Condition! We are a legitimate business specializing in calculator products and are dedicated to accurately and efficiently serving our customers - check our About Me page for details! The small and compact StudMark makes finding a stud easy and dependable. To use, place the StudMark on a wall and move it in a "Z" pattern to find nails or screws used to hold the sheetrock to either metal or wood studs. Its two powerful rare-earth magnets will snap to and hang from the nail or screw head, leaving your hands free to drill, nail or level. Once in place, there are two removable magnetic markers that can be used to identify and mark a stud while the user moves on to locate and mark up to three studs at one time. Or, a pencil mark can be made in the divot located in the tip of the StudMark. Features: Two removable magnetic markers (1 1/2 inches long by 1 inch wide)Two rare-earth magnets in StudMark baseNo moving parts and never requires calibrationNo batteries requiredUnit is 3 1/2 inches long, 1 1/4 inches wide, 7/8 inch tallWeight: 2.3 oz.