Even specifying something like a RAL number is not enough. E.g. powder coatings with the same spec from different manufacturers or even from different lots from

Even specifying something like a RAL number is not enough. E.g. powder coatings with the same spec from different manufacturers or even from different lots from the same manufacturer can look noticeably different if placed next to each other. So in order to get a perfect match you need to coat your stuff from one batch of powder coating.