Pelikan 4001 GTP/5 Ink Cartridges for Fountain Pens, Royal Blue, 1.4ml, 5 Pack (310748) Ink formula developed over 125 years ago protects both fountain pen and nib Bold color ink produces clear line definition with an even flow For pelikan fountain pens and many other brands using ink cartridges 1.4ml of ink in each cartridge Made in Germany