The Magna-Trak MT202 is ergonomically designed for complete one-handed operation so your other hand is free to use other equipment. Easily locate ferrous objects underground, underwater, or in snow. Find PK nails, iron pipes, valve covers, masonry nails, manhole covers, cast iron water and gas lines, surveyors markers and more. The MT202 The MT200 includes a Power Line Indicator as well as an Erase feature that lets you block out magnetic interferences that occur when working next a large metal object such as a chain-link fence.