Sold in six-packs. To fit almost every fountain pen currently in production. Any fountain pen that can take a cartridge or converter usually can take
Monteverde - Ink Cartridge Refills - International Size - Purple - Pack of 6
Round Top European™ Screw Cap Fountain Pen Chrome - Pen Kit Making Supplies Berea HardWoods
PAPERMATE BLUE INK Ballpoint Pen Comfortmate Ultra 0.3mm S0213750 Pack of 12 £12.99 - PicClick UK
PENNA STILOGRAFICA UNO Istyle pennino fine con 2 cartucce di inchiostro extra blu inchiostro a flusso liscio EUR 2,71 - PicClick IT
Colorado Pen International Standard Ink Cartridge (6 per box) – coloradopen
LUXOR INK GLIDE Unique Iridium Tip BLACK BLUE Refillable Fountain Pen Cartridges £2.99 - PicClick UK
Are Fountain Pen Ink Cartridges Universal?, EndlessPens
fountain pen refills products for sale
The Ultimate Guide to Pen Refills
PENGEMS PENGEMS® Ballpoint Refill Ink Cartridges 0.7mm Medium
6 X INTERNATIONAL Standard Size Fountain Pen Ink Cartridges,Monteverde,12 Colour £4.50 - PicClick UK