Private Reserve InkEssentials - Empty Standard Cartridges (50 pcs), Clear (PR2), 1 Count (Pack of 1)

If you are a fountain pen user who likes to experiment with different inks this product is for you. 50 empty standard international clear cartridges allow you to use a blunt syringe to fill and reuse the cartridge.I find these clear cartridges versatile and economical. Allows you to use all your bottled ink without waste and enables you to carry many types of ink. Seal the top of the cartridge with a drop of hot glue. They are reusable and a no-mess solution to custom ink applications.Private Reserve is known for its inks and creative solutions as this empty cartridge package. I believe Private Reserve offers a "cartridge and blunt syringe package" as well.I recommend this Private Reserve product to all DIY fountain pen users.

I use these to share inks with friends who use cartridge "exclusive" fountain pens like the Kaweco Sport. A blunt-needled syringe to fill the cartridge and a small dollop of hot glue on the end to seal it until use and you're off and running. Cartridges can also be reused to help reduce the plastic waste.

I have an Ohto Dude, a Parker Jotter, a Lamy Safari, and a Miju Aluminum. All of these pens - barring the Lamy - accept universal cartridges. No cartridge would fit on these pens. The widest point of the hole seems wide enough to fit over a universal receiver, except there is a lip on the inside that makes the hole smaller. The consequence of this is that it will never fit on a universal pen. This was not a one-off thing either as every other cartridge in the box had the same design flaw.

I was having such a hard time finding empty cartridges that would fit my Kaweco Student pen. Low and behold I stumbled on these and they are perfect!!