The 144, despite being widely called a piston filler, is technically a cartridge or converter fountain pen. For authenticity checking, alongside visual features like star form, Pix embossing and clean laser engraving on the clip, above all comparison with reference photos as well as assessment in a Montblanc boutique, e.g. on Munich's Maximilianstraße, are recommended. A thorough cleaning can often remedy existing function disorders, so that the pen is again usable as a writing instrument.