Super5 bottled inks are waterproof once dry making them ideal for important documents or for sketching. When sketching you can use these inks to create a permanent outline and then fill in watercolour.
Frankfurt is a grey ink.
Available in 6 different colours they are ideal for use with Super5 ink rollerball pens (ink converter needed) or with any fountain pens. They come in 30ml glass bottles or are also available as ink cartridges.
Fountain pens or Super5 ink rollers require the use of an ink converter. You attach this to the pen in the same way as an ink cartridge, then submerge the entire nib in the bottle of Super5 ink. As you squeeze or twist the back end of the converter it will draw the ink inside via the nib. Please repeat the process of squeezing until the converter is full. Then take a paper towel and dry the nib.