ΔE 17.3, loose: different enough that you should pick on purpose. NATO Brown is a little darker, much more muted, warmer than Dark DAK Sand.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). NATO Brown is a little darker, much more muted, warmer than Dark DAK Sand.
The same difference applies the other way round: Dark DAK Sand is a little lighter, much more saturated, cooler.
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 Dark DAK Sand on the colour wheel See NATO Brown on the colour wheel
All matches: Dark DAK Sand equivalents · NATO Brown equivalents