The model is the Waterman 'CF' from 1953, produced until the late 1970s in various versions. The CF needs special cartridges or a hose converter, since Waterman in the 1980s changed the filling mechanism and today's usual cartridges no longer fit. If old cartridges can still be found, they can in a pinch be refilled by hand with a syringe (e.g. obtainable from the family doctor). For deeper research, the Waterman specialist Volker Kirkel is referenced, who advises collectors in detail.