ΔE 6.4, close: similar, with a visible difference side by side. Flanker Blue is a little lighter, cooler than Gray FS36375.
Usually, if you are not matching paint already on the model. Close match (ΔE 6). Flanker Blue is a little lighter, cooler than Gray FS36375.
The same difference applies the other way round: Gray FS36375 is a little darker, warmer.
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 Gray FS36375 on the colour wheel See Flanker Blue on the colour wheel
All matches: Gray FS36375 equivalents · Flanker Blue equivalents