Additional Details ------------------------------ Product description: The M-97 is an all-metal metal detector that can search through concrete and asphalt and was designed for finding buried or paved over valves, boxes, or manhole covers, or any other concealed metallic object. It also locates targets made of aluminum, brass and lead. Please remember, like all Valve and Box Locators, the M-97 is a Metal Detector which should not be used as a substitute for a Utility Line Tracer