SCHMINCKE Masking Fluids
Use these removable fluids to make specific areas water resistant. They will retain areas of white paper or areas of underpainting, then easily rub off with a finger or eraser. The handy dispensing bottle allows for fine detail work.
Dry the surface thoroughly after applying and before painting with watercolours. Do not leave masking fluid longer than two days on the paper. It is also recommended for airbrush work.
Both the blue tinted and colorless masking fluids have the same formulation. These products contain latex.