Magnetic Locator is a proven tool for location of underground utilities and materials. If the material has ferrous in it (if a magnet will stick to it), then these Magnetic Locators will find it, depending on depth and mass of the object. Land Surveyors especially enjoy using this tool for finding rebar and pipe property corners and surveying markers. It can also be used for finding ductile iron water pipes and valve boxes that are buried underground.