As for [[Zerollo]] the pen had limited success, because of the mechanical fragility due to the considerable complexity of the same, and the relative utility of the solution. It was also expensive, so in the end a few were produced, and is therefore one of the most sought after and most expensive French pens. | As for [[Zerollo]] the pen had limited success, because of the mechanical fragility due to the considerable complexity of the same, and the relative utility of the solution. It was also expensive, so in the end a few were produced, and is therefore one of the most sought after and most expensive French pens. |