WATERMAN Fountain Pen Converter, Standard (56010W). Simple plunger-driven ink container refills easily to use liquid ink neatly and conveniently with your fountain pen. Liquid ink is smooth-flowing, leaves a solid, confident line, and adds to the sophisticated experience of fountain pen use. This converter fits all WATERMAN fountain pens sold in the U.S. Using a refillable converter rather than disposable ink cartridges saves money and reduces waste.