Tom's Studio - Fountain Pen Nib - Pro-Flex

Pro-Flex Fountain Pen Nib

A gamechanging, flexible fountain pen nib.

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Ultimate flexibility, this is a cut above your standard flex nib.

This is a professional grade nib so please make sure you understand your purchase by reading the DETAILS section before ordering.

My Pro-Flex Nib (PATENT PENDING) has been designed from the ground up and has a few novel features which separate it from the your standard flex nib:

The Pro-Flex is fitted with a Titanium Coated Zebra G calligraphy nib, this is the cream of the crop when it comes to calligraphy nibs and gives you the finest of fine strokes and the juiciest of thicker strokes. It's perfect for drawing, calligraphy and just putting pen to paper. It flexes from hairline to 2mm.

A new ink delivery system, the feed (which delivers the ink) is designed to stay in contact with the nib. It does this by having an integrated 'leaf spring'  which means that the feed flexes when the nib does!  Most flex pens fail when the feed loses contact with the nib but this invention means that it will always deliver a consistent amount of ink.

This snazzy little feature also acts like a 'sump' which stores excess ink and releases it when the nib needs it.


Made to work in all of my fountain pens, the housing is a Bock 250 size 6, which is common to many lovely tools.

Most fountain pen nibs are made from stainless steel, which is highly resistant to corrosion but is also extremely hard. Calligraphy nibs, on the other hand, are made from softer, springier alloys that allow them to flex with very little pressure. The trade-off is that these alloys corrode over time. However, the titanium coating protects the nib and makes it last up to six times longer than a standard nib. Once your nib eventually wears out, you can remove it with pliers and replace it with a new one.

This is a very juicy nib, which is amazing for performance but can occasionally cause the nib to leak when you don't intend it to. If this happens, just remove the cartridge or converter before travelling or storing.

A very frustrating feature of eye-dropper pens is that they sometimes suffer from 'ink burping' (very unpleasant!). This is a mystery that even the greatest minds are still trying to decipher, but it can mean that ink-hungry nibs like the pro-flex can be affected by inconsistent ink flow. If this happens, it may be worth reverting to an ink cartridge or converter.

We aim to process your order within 1-3 working days. Please note that this increases to 1-4 working days for orders that include any personalisation, such as engraving.

Shipping costs

Shipping costs are calculated at checkout.

Delivery times

  • UK: 1-2 business days
  • Europe: 3-5 business days
  • USA: 5-7 business days
  • Rest of world: 8-10 business days (duties may apply on delivery)

Please refer to our Delivery page for more information, and reach out to us at if you have any further questions.

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Customer Reviews

Based on 22 reviews

Always a perfect nib. Thank you so much. And for the tea also xoxo


Lovely quality as expected. Thank you Tom.


This is my go-to nib for illustrations

Max S.
A true game changer

The ability to use a proper calligraphy nib without having to continuously stop to redip, as well as the ability not to worry about ink blotting or running out if ink halfway through a character, is revolutionary. Coupled with the fact that this feeder will take any of your existing nibs, this is a must have for anyone who uses dip pens as a core tool - or who wants to do more pen and ink work but struggles with the logistics!

If this is your first foray, remember to sand the nip-tip a tiny amount to make it run smoothly.

Truly incredible.


It is scratchy compared to modern fountain pen nibs, but works extremely well! The feedback of the nib matches dip pens so I don’t consider it a negative, but something to let other buyers know.