Often, we find ourselves having to make mixes of pigments and/or thinners in specific ratios. If you are very experienced, or a small deviation is not critical, you can eyeball it.
But sometimes is not, and if you want a specific color you have to mix two others in a 60/40 ratio, or you need to thin paint with a ratio of 50% paint to 50% thinner to achieve the perfect consistency.
The way that offers the best accuracy vs. price relationship is using pipettes.
With these sets of different numbers of pipettes, you can achieve excellent results, thanks to their measurement markings.
We have to prepare each shipment individually as they are ordered, so allow it in 3-4 weeks to arrive in the USA/Canada (to be safe) and 3-6 weeks rest of the world, though they are usually delivered much faster.