ΔE 7.9, close: similar, with a visible difference side by side. Russian AF Grey N.4 is more muted, warmer than Contagion Green.
Usually, if you are not matching paint already on the model. Close match (ΔE 8). Russian AF Grey N.4 is more muted, warmer than Contagion Green.
The same difference applies the other way round: Contagion Green is 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 Contagion Green on the colour wheel See Russian AF Grey N.4 on the colour wheel
All matches: Contagion Green equivalents · Russian AF Grey N.4 equivalents