![Rotring Isograph Pen Nib thumbnail](https://dbot7h6zuj3cx.cloudfront.net/9/1/images/catalog/i/m_14190-PP_ISOGRAPH_NIB_super.jpg)
Replacement Nib for Rotring Rapidograph Pens for tracing paper, vellum drawing paper and lineboard.
The rapidograph uses rotring’s unique capillary cartridge. The pressure-equalization system, including ink helix is part of the ink cartridge which ensures that every time you change the cartridge, you get a clean new ink helix. This means that you never need to clean the ink helix and top reliability is guaranteed.