Winsor & Newton Promarker Watercolour is a marker filled with transparent watercolor ink. The ink uses pigments, so the colors are bright and resist fading in light. Each marker has two tips: a fine bullet tip and a brush tip.
The range has 36 colors. You can buy single markers, and there are also sets of 6 and 12 colors.
You can layer the colors and blend them into each other. Run a wet brush over a marker line and the color dissolves, so you can soften it like a watercolor painting. You can also use the markers together with Winsor & Newton watercolor paints.