The ElektroPhysik 80-137-5800 MiniTest 735 Coating Thickness Gauge FN5 HDF, Ferrous & Non-Ferrous Metals, 200 Mils / 5000 Microns.(Heavy Duty) Modification: Flat Pole Probe (dia. 9mm) is the solution to all your coating thickness problems where a reliable finish and perfect product appearance play a major role for long-term value and success, e.g. in the automotive and shipbuilding industry, steel- and bridge construction or in the electroplating industry, to name a few industries.