This fountain pen is the result of Dante Davide Zerollo’s idea to create a piece that would be two pens in one. Technically, it is a piece of great complexity.
Its mechanism allows for the extraction and retraction of two nibs while accessing, through two different openings, the corresponding ink sac for each one, distinguished by their colors – one red and the other blue.
To apply pressure to the ink sac, a punch attached to the top of the fountain pen must be inserted, which can be unscrewed from the cap.
This pen, dating back to the 1930s, had three different manufacturers.
The first was Dante Zerollo himself. It has not been clarified whether it was made in his workshop or if he used Armando Simoni’s workshop (Omas). Authors have not agreed on this matter. Zerollo’s workshop was located at Vía Baradino, 19, in Genoa.
The second was the French company Unic, which named the model “Duocolor.”
The third was the English company John Dunhill, which introduced it as the “Two Pen.”
This pen was released in various celluloid finishes and also with a gold “sleeve.”
The production of this type of pen spanned most of the 1930s and the beginning of the 1940s.
It is a sought-after piece in collecting circles, not only for its technical variety but also for its scarcity in the market. This is mainly due to both the limited number produced and the mechanical issues that arose due to the complexity of its design.
