Masking without leaving any residue: applying masking fluid has never been so easy. With the ready-to-use masking fluid pen, you can draw precise lines – without a brush. This creates white outlines and recesses on almost all surfaces. The dried masking fluid can be painted over using the pen on almost all dried acrylic, water or alcohol-based inks. After drying, the tinted masking fluid can be removed without leaving any residue for up to two days.