Graphene Gray vs Grey Green RLM74

How close are they?

ΔE 8.1, close: similar, with a visible difference side by side. Grey Green RLM74 is a little lighter than Graphene Gray.

Can I use Grey Green RLM74 instead of Graphene Gray?

Usually, if you are not matching paint already on the model. Close match (ΔE 8). Grey Green RLM74 is a little lighter than Graphene Gray.

Can I use Graphene Gray instead of Grey Green RLM74?

The same difference applies the other way round: Graphene Gray is a little darker.

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.