Pebeo Drawing Gum (Masking Fluid)
This removable liquid frisket for watercolour and airbrush is water soluble when wet, but dries waterproof. Drying takes about 15 minutes depending on quantity used and surface. Apply with a brush, colour shaper or pen on parts of the design to hide. The colouring is done after complete drying of the Drawing Gum.
To discover the parts that have been hidden, simply remove the Drawing Gum with a finger or an eraser, when the colours are perfectly dry.