Ink Cartridges Blue Six Packets. The 0125 ink cartridges are suitable for all Waldmann Fountain Pens, apart from the `Manager` as this fountain pen has a built-in piston filling system. Each packet contains 6 cartridges. Please note minimum order quantity for packets of ink cartridges is qty 6. This is reflected in the price stated. When buying a Waldmann Fountain Pen, you will be able to order just one packet of cartridges.