Extra Dark Seagray BS381C 640 vs Engine Gray

How close are they?

ΔE 6.2, close: similar, with a visible difference side by side. Engine Gray is a little lighter, warmer than Extra Dark Seagray BS381C 640.

Can I use Engine Gray instead of Extra Dark Seagray BS381C 640?

Usually, if you are not matching paint already on the model. Close match (ΔE 6). Engine Gray is a little lighter, warmer than Extra Dark Seagray BS381C 640.

Can I use Extra Dark Seagray BS381C 640 instead of Engine Gray?

The same difference applies the other way round: Extra Dark Seagray BS381C 640 is a little darker, 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.