Thanks for the feedback, fordmar.
Your scene was set to Centimeter, perhaps try inches in the Project Settings> Scale, Or check the Preferences> Units.
Don't worry; even last week, I couldn't directly pinpoint if an M2 or M2.5 screw/bolt or a #2-56-3/8" went missing on my Follow Focus. It was the latter. (I measured 2.2 mm, so I searched. But I have never heard about 2-56 UNC)
I find the Inch with decimal points (instead of fractions) confusing, even after being in California for 18 years. I think growing up in one system leaves a mark.
Cheers