Use Holbein Acrylic Ink to create bold, brilliant color with a brush, airbrush, dip pen, technical, or refillable markers, or to achieve the subtle characteristics, washes, and tones of watercolor painting. It will not clog a 0.1 mm aperture. Compatible with all Holbein waterbased media. - Holbein Acrylic Ink - Opaque Medium, 100 mlHolbein Acrylic Ink, OPAQUE MEDIUM 100ML -