Kaweco Royal Blue is a washable ink for fountain pens. It could be easily washed out of the paper or erased with a special eraser. It also could be removed from clothes and different surfaces in case of any ink-related accidents.
Many brands offer royal blue inks. Kaweco's version, however, is slightly different — it has a barely noticeable purple undertone to it.
Kaweco Royal Blue dries pretty quick on most papers and has a good, moderate flow. It will work well in all fountain pens, new and vintage.
Kaweco decants this ink into handy 30ml glass bottles which could be turned on their side to help with filling when the ink level runs low.