Set of 10 TWSBI Sapphire Blue ink cartridges.
These ink cartridges are made to fit the TWSBI SWIPE fountain pen. Our experience has found that they do not fit in other pens, because they are a bit longer and wider than a typical standard international size.
- Ink Cartridges
- Max Ink Capacity - Cartridge
The maximum volume of ink that can fit in the pen when using a cartridge.
- Cartridge Type
- Number of Cartridges
- Fast Drying
Whether or not the ink contains glittery particles.
- Freeze Resistant
Whether or not an ink is specially formulated to better withstand freezing temperatures.
- Iron Gall
Ink made from iron salts and tannic acids. Though quite permanent and waterproof, these inks are typically known for causing chemical corrosion to metal pen parts (especially the nib) and should be used sparingly or with less-valuable pens.
Whether or not an ink is specially formulated to increase flow in your pen.
Whether or not the ink contains finely-ground solid particles in liquid suspension.
- Water Resistant
Whether or not the ink, once dried on the paper, will resist being washed away with water.
What fountain pens are compatible with ink cartridges?
There are two main groups of ink cartridges: standard international (available in short and long sizes), and proprietary (which only fit that particular brand). You can read which cartridges fit a given fountain pen in that pen's product description or Tech Specs.
You can also check out our Cartridge/Converter guide for general brand guidance if you’re unsure.
To locate pens that fit each size of ink cartridges, click here:
How do I install an ink cartridge?
Check out our Fountain Pen 101 video on Ink Cartridges to see an overview how they work.
Here's another video example using a LAMY ink cartridge, though the technique is the same across other brands.
Can I refill an ink cartridge?
Yes! You'll need an ink syringe, but it's pretty easy to do. Check out this video to watch how:
Do ink cartridges generally write more dry than bottled ink?
Yes, they do.
What's your return policy?
We do not accept returns for ink that has been used. Otherwise, we accept returns on unused ink products for up to 60 days from purchase. You can read all our Return Policies here.
To initiate a return, please submit a request at the Return Portal. Our Customer Care team might reach out to you for more information.