ΔE 6.7, close: similar, with a visible difference side by side. Cam. Black Brown is a little lighter than NATO Black.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Cam. Black Brown is a little lighter than NATO Black.
The same difference applies the other way round: NATO Black is a little darker.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See NATO Black on the colour wheel See Cam. Black Brown on the colour wheel
All matches: NATO Black equivalents · Cam. Black Brown equivalents