ST Dupont is a late comer to the world of fountain pens. They first entered the luxury pen market in the early 1970s with a line of elegant, slim ball points called the "Classique". Soon they added a matching fountain pen.
The pens of the period were generally slim and the ST Dupont Classique was among the slimmest.
From left to right: Parker 75, Waterman Preface, Montblanc 144, ST Dupont Classique, ST Dupont Gatsby, Parker 95.
The only drawbacks to the Classique series was that the section, the part that you held to write had to be even slimmer than the cap to fit inside and so writing with it over extended periods often led to hand cramps and that the cap when posted could irritate the webbing of your hand.
ST Dupont then issued their next series, the Gatsby, and addressed those two issues in a classically innovative way. It was a great example of ST Dupont's attention to detail at even the most mundane level.
Two Gatsby fountain pens.
The way ST Dupont solved the problems found in the Classique series was to place the section completely inside the body so that you held the body itself. Although the overall difference in girth seems little it mad an enormous difference in the feel and comfort when writing over extended periods. The cap itself was inserted INTO the body when closed or when posted.
As with all ST Dupont products, the attention to detail is outstanding. The pens, whether Chinese Lacquer or precious metal finishes are warm to hand and offer great tactile control and feel. The cap slips on with a positive 'click' and is always secure. Even after years of daily use they continue to perform flawlessly.