The German QNix NFe5mm Thickness Gauge probe is an eddy current coating Thickness Gauge probe with a thickness measurement range of 0~5000 microns. The NFe5mm Thickness Gauge probe is a matching probe for the QNix7500 anti-corrosion layer Thickness Gauge, with a measurement accuracy of 0~1999 μm. : ±(1μm+2%); 2000~5000μm: ±3.5%.

| model | Fe-2000 | Fe-5000 | Nfe-2000 | Nfe-5000 | Fe/Nfe-2000 | Fe/Nfe-5000 |
| matrix | iron | iron | non-iron | non-iron | Iron/non-iron | Iron/non-iron |
| Probe form | Integrated/split | Integrated/split | Integrated/split | Integrated/split | Integrated/split | Integrated/split |
| Measuring range | 0~2000μm | 0~5000μm | 0~2000μm | 0~5000μm | 0~2000μm | 0~5000μm |
| measurement accuracy | 0~1999μm: ±(1μm+2%) | 0~1999μm: ±(1μm+2%) ; 2000~5000μm: ±3.5% | 0~1999μm: ±(1μm+2%) | 0~1999μm: ±(1μm+2%) ; 2000~5000μm: ±3.5% | 0~1999μm: ±(1μm+2%) | 0~1999μm: ±(1μm+2%) ; 2000~5000μm: ±3.5% |
| Minimum measuring surface | Fe: Ï25mm; NFe: Ï25mm | |||||
| Minimum radius of curvature | Convex surface Ï5mm, concave surface Ï25mm | |||||
| Minimum substrate thickness | Fe: 200μm; NFe: 50μm | |||||