The Nix Qnix NFe3mm thickness probe uses the eddy Current thickness measurement principle, with a thickness measurement range of 0 to 3000 μm. Measurement accuracy is +/- (2 µm + 2% of the reading) at < 2.0mm; +/- 3% of the reading at > 2.0mm. It is an optional nonmagnetic probe for the Qnix5500 and Qnix9500 series Thickness Gauges.