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

A gamechanging, flexible fountain pen nib.

Ultimate Flexibility

FYI, this is a professional grade nib so please make sure you understand your purchase by reading the GOOD TO KNOW section before ordering.

My Pro-Flex Nib (PATENT PENDING) has been designed from the ground up and has a few novel features which seperate 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.



  • Most fountain pen nibs are made from Stainless steel which is super resistant to corrosion but is also hard as nails. Calligraphy nibs are made from softer, springier alloys, which allow them to flex with very little pressure.  The tradeoff is that they corrode over time.  However, the Titanium coating protects the nib and makes it last up to 6x longer than a standard nib. Once your nib eventually does bite the dust, you can remove it with pliers and replace with a new nib available here

  • This is a very juicy nib, which is amazing when it comes to performance but can on occasion cause the nib to leak when you're not intending it to. If this happens, just remove the cartridge or convertor before traveling or storing. I will be making stoppers for your cartridges soon too!

  • A very frustrating feature of eye-dropper pens is that they on occasion suffer from something called 'ink burping' (very unpleasant :) ). This is a mystery, 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 convertor.
  • Made to work in all of my fountain pens, the housing is a Bock 250 size 6 which is common to lots of lovely tools.

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 21 reviews

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.

Derek D.
Pro Flex Nib

Very good unit with amazing flex. Cheap to replace the nibs