Universal Drawing inks are suitable for a variety of applications including use in technical pens and refillable plotting points.White and black are opaque, other colours are transparent.For use on paper and film.Waterproof.#3080-F.Rapidraw is a fast drying waterproof ink for film.Erasable on film, short open pen time.Good ink for experienced technical pen users.#3084-F.Ultradraw ink is for use on paper and features slow drying ink for long open pen time.Good for beginning technical pen users.#3085.All inks 90ml with easy fill spouts.