The Laserliner Metalli Finder Pro is an electronic device with LCD depth display for easy detection of ironsolid bar copperwater pipes & voltage warning within wall & masonry The depth measurement function aids in deciding where sufficient drilling depth is available A centre indication LCD light pin points the centre of an object The user guide on the LCD screen makes it accurate & reliable to use The Metalli Finder Pro has an auto-calibration which automatically adjusts the device immediately to different surfaces An acoustic signal sound & visual will signal the location of objects High voltage warning signal is always in function Supplied with 1 x 9V battery Depth Range Iron Solid Bar Up to 75cm Copper Water Pipe Up to 5cm Live Electric Up to 4cm