Xezo Pens International Standard Size Black Ink Cartridges for Fountain Pens, 10-Pack, Black Ink (Black&nbsp;Fountain&nbsp;Cartridges) Black ink. Pack of 10 cartridges. Standard European / International size. Fits all Xezo fountain pens. Fits other pens that accept Montblanc standard fountain ink cartridges. Black Ink Standard European / International Size Pack of 10 Cartridges