Hi Martin and Michael,

I opened the file in NX and it come in as an Imperial file, I also noticed these statements in the STEP file

#36=UNCERTAINTY_MEASURE_WITH_UNIT(LENGTH_MEASURE(1.0E-006),#38,'','');
#38= (CONVERSION_BASED_UNIT('INCH',#70)LENGTH_UNIT()NAMED_UNIT(#73));

but further down it has this;

#119= (NAMED_UNIT(#73)LENGTH_UNIT()SI_UNIT(.MILLI.,.METRE.));

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