ΔE 9.3, close: similar, with a visible difference side by side. Light Blue is a little lighter, more muted than Gray FS26440.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Light Blue is a little lighter, more muted than Gray FS26440.
The same difference applies the other way round: Gray FS26440 is a little darker, more saturated.
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 FS26440 on the colour wheel See Light Blue on the colour wheel
All matches: Gray FS26440 equivalents · Light Blue equivalents