Pen can be filled by different methods. In the United States, patents have been issued for Button, Click, Lever Matchstick methods and spare parts. All these methods have been used to put a little pressure and deflate the bag or internal plate to allow ink to flow in and out. The vintage pens eyedropper May need filling. There are self-filling pens that have a bag in the pens.

When pressing the bag, the pen is filled or empty of ink. The last method is to use international cartridges or cartridges; cartridges are known as cartridges because of the large number of European companies that use them in fountain pens. This method uses a piston in the enclosure, which focuses on the top or bottom inside of the barrel of the pen by twisting a button on the end of the pen. Today, most pens are use of piston filling cartridges. There are some converters that can convert the pen refill cartridge to a piston recharge.

The drops of ink filling pens have the maximum capacity to hold the ink, with the least amount of resources allocated to the piston pen refills. The piston sometimes occupies half of the pen barrel, leaving less space for holding the ink. But the method could be messy eyedropper.

International cartridges of all brands can be used in some fountain pens, while others accept only their own cartridges brand. There are fountain pens in which a converter cannot be good. The only way to use ink in the pen is to fill the cartridge with a syringe. There is a wide range of inks that you can choose from when filling a pen. Ink bottles of various shapes and designs are in the tender. Some users like the idea of filling a cartridge of a pen by themselves, even if it means doing a little disorder in the ink.

Pens are people who give not only the joy of fine writing, but also serve as a collection. Pens are generally more expensive compared to the regular disposal of the plant ball. Accordingly, ballpoint pens are popular for everyday use in people who cannot afford such expensive pens for regular use.