Modifiche

[[Zerollo]] produced substantially only one model, albeit in a considerable number of variants, called [[Zerollo|Duo Color]] precisely by its characteristics of beeing made by two internal separate pens allowing to write in two different colors. The mechanism, which incorporates the technology used on the classic [[safety]] pens is extremely sophisticated and bears close tolerances, which makes the pen rather weak in terms of mechanical stability. Through an ingenious screw system, the two pens, which are separated by a metal plate attached to the bottom that makes them rotate, are slidnf in opposite directions by means of grooves made ​​in the body of the pen, and brought alternately inside and outside the body according to the direction in which you rotate the cap.  

[[Zerollo]] produced substantially only one model, albeit in a considerable number of variants, called [[Zerollo|Duo Color]] precisely by its characteristics of beeing made by two internal separate pens allowing to write in two different colors. The mechanism, which incorporates the technology used on the classic [[safety]] pens is extremely sophisticated and bears close tolerances, which makes the pen rather weak in terms of mechanical stability. Through an ingenious screw system, the two pens, which are separated by a metal plate attached to the bottom that makes them rotate, are slidnf in opposite directions by means of grooves made ​​in the body of the pen, and brought alternately inside and outside the body according to the direction in which you rotate the cap.  

Per scrivere è necessario estrarre completamente una delle due penne dal corpo, portando l'altra all'interno, in posizione di riposo queste invece devono essere poste alla stessa altezza restando parzialmente sporgenti dalla apertura anteriore, ed in questa posizione è possibile sia chiudere la penna col cappuccio che eseguire il caricamento. Il cappuccio infatti ha il solo scopo di protezione delle punte delle due penne, dato che l'inchiostro non è contenuto nel corpo ma nelle singole penne che sono alloggiate in esso.

To write is necessary to completely extract one of the two pens from the body, bringing the other inside. In the rest position instead the two pens must be placed at the same height remaining partially protruding from the front opening, and only in this position it is possible to close the pen putting the cap and refill them. The cap has in fact only the purpose of protection of the tips of two pens, since the ink is not contained in the barrel body but in the individual pens that are housed in it.

[[Image:1933-12-Zerollo.jpg|thumb|left|Pubblicità [[Zerollo]] del 1933.]]

[[Image:1933-12-Zerollo.jpg|thumb|left|Pubblicità [[Zerollo]] del 1933.]]