Asvine Fountain Pen Ink Cartridges Black Color, Set of 30 Refill Ink Cartridges, 3.4 mm Bore Diameter
Brand: Asvine
Color: Black

Notice: These cartridges are not Standard Size, Please ensure your fountain pen takes 3.4mm bore diameter cartridges.
You may like the cartridges filler converter below:
www.amazon.com/gp/product/B08LLFVQVV
How to fill a fountain pen with cartridges:
Insert the narrow end of the new cartridge into the black of section block with enough pressure to create a snug fit. The pin inside the section block will puncture the seal of the cartridges, allowing ink to flow into the section block. Screw the barrel on over the cartridge into the section block.
When you fill the pen at the first time, you can swing the pen to make a few drops of ink coming out of the nib, so that it can flow easily.
100% Satisfaction Guarantee:
If the cartridges you received are not in satisfied condition, please feel free to contact, we will fix the problem for you.

✅ LARGER PACK: 30 pack of 3.4 mm bore diameter black ink cartridges ( compatible with fountain pens take 3.4mm cartridges such as hongdian ). Notice: These cartridges are not Standard Size.
✅ DIMENSION: Length Appr 51mm; Cartridge Diameter Appr4-7mm; bore diameter 3.4mm
✅ SMOOTH INK FLOW: With no break in ink flow, enjoy a smooth and optimal writing experience as your fountain pen glides elegantly across paper.
✅ NEUTRAL PH & NON-TOXIC: The ink has been carefully manufactured using only natural dyes giving the composition a neutral, natural, and non-toxic PH.
✅ QUICK TO DRY: HongDian Designs ink takes only a few seconds to dry ensuring your important writing moments are not ruined by smudges or smears.