Our pens were designed to be used with an International Standard converter.

However, we have done some tests and it seems that they can be used with International Standard or International Short cartridges.

Be sure to manually push the cartridge into the grip section to successfully puncture the cartridge.

DISCLAIMER: As with any fountain pen that was not specifically designed to be an eyedropper pen, the user makes this conversion at their own risk.

That said, we tested one Blossom pen and one Heartwood pen. We used both silicone grease and a rubber o-ring on both pens to get the best seal possible. The measurements for the o-ring that we used are: 1mm thick, 9.5mm inside diameter, 11mm outside diameter.

We carried the pens around for several days to ensure they did not leak and we used the pens for a few weeks to ensure they still had good inflow. Our test was successful.

For our testing we used Lamy Blue/Black ink. It did not stain, though we did not do a long-term test.

Most standard, water-based inks should not stain the acrylic resin. However, some highly saturated or pigmented inks may tint or stain the pen, particularly the lighter-colored resins. When in doubt, look it up—there are likely posts and reviews online regarding the specific ink you are wondering about.

We use Alumilite acrylic resin, which is made in Kalamazoo, Michigan.

The small batch nature of our pens doesn’t mean we won’t make more of a colorway. Feel free to reach out and ask us about the specific colorway.

Unfortunately, the discounts for the included steel nib and free shipping are not itemized.