I like Koh-I-Noor stuff but this has been a disaster. 1) I bought it for technical pen use; it clogged EVERY technical pen I put some in and two of those I consider total write-offs now, and I've used these pens for decades! 2) The cap has a built-in dropper that can't be used to cleanly fill the tech pen reservoir tubes -- it's just too clumsy. 3) So I took off the cap to access the ink with a syringe, and that was a mistake. I don't know if it was from shaking the jar or just a poor design, but ink was everywhere it shouldn't be for an art product. I had to wash the cap and the bottle sides before putting it back on. Anyway, I blame K-I-H and not DEW at all.