Sewerin Brand Metal and Ferromagnetic Object detection locators
The Sewerin M-130 is a basic metal detector designed and optimized for finding valve boxes, meter boxes, curb boxes, and other metal objects. I can also find non ferrous objects such as brass, aluminum, and copper
The FerroTec FT10 is a ferrous metal detector, or magnetometer. It will find only ferrous metals and magnetic objects. It can also indicate polarity of the objects to determine size and orientation. It can also indicate 50Hz or 60Hz signals indicating live electrical wires.