Dr.meter Fi-1 Backlight Stud Metal AC Wire Scanner Wall Stud Finder Electronic StudSensor, Yellow Ergonomic Design: Compact handheld body and anti-slip design, convenient to use as a handy household device Smart beep feature- Comes with an audible beep feature that sounds reminding you of the stud's position/location LCD Backlit Display and Audible Indication: Illuminated graphical LCD and sound signal indicate mode, detection strength and more Multi-mode Detection: Detects metal studs up to 3/2 in(38mm), metal rebar or pipe up to 3 in(76mm) while AC live wire up to 3 in(76mm) Functionality: Quickly locates edges and center of metal studs, pipes, rebars, joists behind walls, floors and ceilings, also indicates the presence of live AC wire