FPR-FNF #6 Chrome Ultra Flex JoWo Compatible Nib Unit (ebonite feed)

Imprescindible si te gusta dibujar. Buen precio, muy buena compra.

This flexes really nicely with little pressure. It was plug and play in my Mad Science Pen Company's Beta-R pen. This pen has a very large TWSBI converter in it to provide lots of ink.

FPR-FNF #6 Chrome Ultra Flex JoWo Compatible Nib Unit (ebonite feed)

I have purchased both the plastic feed and the ebonite versions and, from my experience, the ebonite is leagues ahead. Ink flow is wet and consistent with no railroading, even with fast, every-day type writing. Exceptionally pleased with this one!