To fit a wide range of fountain pens.
Euro fountain pen cartridges are a minefield. Many pens sold today like Laban, Sigma and many general brands found in the High Street take the euro style cartridge, up until now the ink could often be of indifferent quality causing flow problems to your fountain pen, but these ink cartridges are filled with genuine Diamine Ink and you have a choice of sixteen colours. Pack of 18.
To view colours, click on 'Ink, Refills and Convertors' then 'Diamine Ink' in main screen.