A very useful instrument for tracing pipes detecting nails & screws etc. in walls. In addition to detecting metals it can also detect electric cables that are connected to the mains even if no current is flowing. To distinguish between metal objects & mains cables an LED indicator & buzzer will give a continuous tone & light for metal objects & an intermittent tone & flashing light for mains cable. The detector is housed in a tough plastic case & is powered by one 9V PP3 battery Order Code AR46.