Hongdian Fountain Pen Ink Cartridges Black Color Set, Pack of 30 Ink Refill Cartridges, 3.4 mm Bore Diameter

• [ LARGER PACK ]: 30 pack of 3.4 mm bore diameter black ink cartridges ( compatible with fountain pens take 3.4mm cartridges such as hongdian)
• [ DIMENSION ]: Length Appr 51mm; Cartridge Diameter Appr 4-7mm; bore diameter 3.4mm
• [ 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.
• [ EASY TO WRITE ]: With no break in ink flow, enjoy a smooth and optimal writing experience as your fountain pen glides elegantly across paper.

These cartridges compatible with fountain pen takes 3.4mm cartridges such as Hongdian matte black forest fountain pen 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. Notice: It can take a while for the ink to fully saturate the pen, so don’t worry if it doesn’t start writing right away. You can swing the pen to make a few drops of ink coming out of the nib, so that it can flow easily. 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.