Leptoskop'es are, for decades, well-approved coating thickness gauges for non-destructive measurement of layers upon metals based on the magnetic-inductive procedure (EN ISO 2178) and the eddy current procedure (EN ISO 2360). Pocket-LEPTOSKOP'es are equipped with integrated probes (Fe-probe, or alternatively, Fe/NFe dual-use probe). All other LEPTOSKOP'es are working with external (exchangeable) probes, which are designed either for Fe- or for NFe-operation.