How to Fill a CON-40

Few fountain pen accessories generate more online vituperation than Pilot’s CON-40 converter.1 It’s small and hard to fill completely: it has no capacity. The size complaint is a bit unfair: it’s designed to fit all2 of Pilot’s fountain pens, including the pocket-sized E95s/Elite. Whereas Kaweco and Sailor both make pens that are too small for their standard converters. As for being hard to fill? Between us Jen and I currently have a total of 11 pens with a CON-40 converter, and while they’re not as easy to fill completely as pens with the CON-70 converter3 or piston-filling pens, it can be done. There’s a trick to it, though, and Brian Goulet’s video above shows how to do it.


  1. A converter enables a fountain pen that uses cartridges to use bottled ink.
  2. Almost all: the Custom Heritage 92 is a piston-filler and the Custom 823 is a vac filler, and at least one of the hyper-expensive Namiki pens is an eyedrop filler. A converter isn’t necessary for these pens.
  3. Which is, for the record, much harder to clean.