If you are looking for professional ink to refill your favorite fountain pen, you are in the right place. We have created long-lasting, eco-friendly fountain pen cartridges to provide you with a fantastic handwriting experience. 

Are you tired of reordering your ink cartridges so often? We offer big fountain pen cartridge packs to ensure that you won’t run out of ink to quickly. Our cartridges are perfect for both professional and everyday artistic use, with affordable prices and convenient online shopping options.

The main benefits of any fountain pen cartridge by Zenzoi are:

  • Non-toxic composition – our ink contains no harsh chemicals and has a neutral PH scale, making it safe to use;
  • High-quality ink – our special smooth formula guarantees great flow with each stroke;
  • International size – all cartridges come in a standard size so they will fit almost any fountain pen you choose;
  • Planet-friendly manufacturing – we avoid harmful plastic and use only eco-friendly materials caring about the Earth;
  • Great selection – our online shop offers a variety of choices: From classic black colors to bright colored summer collections;
  • Big packages – there is no need to buy several small sets, just purchase one 24-cartridge pack and enjoy great ink for a long time.


Common types of fountain pen cartridges

International Size Ink Cartridge Refill

cartridge for pen

 Although International Standard Size Cartridges have the same size (1.5" or 3.81cm), the suction part of the cartridge can vary on length. Zenzoi Premium Fountain Pens use 2.3mm long suctions feed, made for German nibs.  This type of cartridges can be use in all other Zenzoi Fountain Pens

You should be able to easily recognize these proprietary cartridges as their shape or size does not meet international standard, is odd and fits just one brand selling them. Some examples are below. 


Examples of non-standard ink cartridges that would fit only

The Brand That Makes Them

fountain pen cartridge
fountain pen ink cartridge


Final Tip

When buying ink cartridges for your ZenZoi™ pen please get cartridges shown above and stay away from branded ones as they often fit only one particular brand that sells them (typical practice of some brands to lock users with their brand).

If you are inserting the very first cartridge into your pen, shake it downwards to start the ink flow. Remember that ink drops make nasty stains, so do this above the safe surface (a kitchen sink or a sheet of paper).