Eco-Line Blush Pens are a brush pen type color marker using water-based dye ink made by Royal Turrence Holland Company.
The ink uses water-based dye inks, so you can get very vivid colors and are recommended for illustrations, designs, comics, calligraphy, etc.
In addition, since it is water-soluble ink, you can use a variety of methods and expressions using a special blender or water, and use blurring on the screen. High transparency and excellent color fastness make it ideal for your printed manuscript.
Eco-Line is a product that complies with European safety standards (EC guidelines) so you can use it with confidence.
5 Primary Colors Set: Lemon Yellow, Magenta, Sky Blue (Cyan), Black, Blender

(From Amazon.co.jp)