I promised a drawing of my water brush pen.
I had two of these water brush pens. They were marketed as ink brush pens. I finally threw one of them away when I found the brush end stuck in the cap far too often. the flow of ink was extremely hard to control and the brush tip was poorly shaped for creating flowing lines of variable thickness. It works far better as a water brush pen. However….. I like the Kuretake water brush pens better. They are easy to use, they don’t leak and the brush is well formed.
Drawing: Noodler’s Flex Pen filled with Noodler’s Marine Green Ink and (I don’t remember the name of the manufacturer and it’s not marked on the pen) metal water brush pen.