Metrotech
Metrotech 880B Magnetic
Locator Repair
Manufactured by Metrotech in the USA.
OEM parts readily available for these units and quite reasonably priced compared to other brands. Except for the knob, which is custom made for this unit. A less expensive non-OEM knob can be used as well.
We have also been successful with repairs on these units using after-market parts.