These versatile nylon-tipped brush pens from Pentel allow you to fill the barrel with any water-soluble medium (water-soluble inks, watercolours or gouache) to use for lettering or painting.
Alternatively, you can just use water, and pick up watercolour or gouache colour from your palette to create great wash effects. You can control the density of colour by squeezing on the barrel of the Pentel brush pen to make the brush wetter or drier.
It's also an ideal companion for the watercolour pencil artist. Using a water filled barrel you can create imaginative blends and washes with your watercolour pencils. This Pentel Aquash water brush set includes three nib sizes: fine, medium and broad.