There are certain watches that define a brand, informing its design ethos and becoming nothing short of iconic in the minds of collectors.

For Audemars Piguet, that watch is the Royal Oak—in all its multitudinous incarnations.

Yet the manufacture from Le Brassus did not earn its seat in the triumvirate of leading watch brands—the so-called Big Three—on the success of the Royal Oak alone.

In fact, both Jules Audemars and Edward Piguet came from long lines of watchmakers, and made their reputations long before the Royal Oak was conceived.

Their reputation rested on watches like this one.

Though not bearing a catchy name like the Royal Oak, or boasting complicated movements like the present-day Jules Audemars collection, this dress watch nevertheless captures everything that Audemars Piguet has come to be.

What stands out the most is the airy thinness of the case—while it can’t be any farther removed from the bulkiness of the Royal Oak Offshore, making ultra-thin watches is something at which Audemars Piguet has long excelled.

Starting in the 1920s, manufactures have vied against each other to create the thinnest watches available on the market. The fiercest competition was between Audemars Piguet and Jaeger-LeCoultre, who fired the opening salvo with the 1907 release of a pocket watch movement that was 1.38mm thin. A mere two decades later (which is almost an instant in an industry where research and development can take years), Audemars Piguet introduced a movement that was 1.32mm thin.

And the competition continues even to this day, with watches like this one—with its thin platinum case—exemplifying the manufacture’s skill at producing thin watches.

Because making a large watch doesn’t require any display of skill. However, making a thin one does. For a watchmaker an ultra-thin watch is the ultimate mark of refinement, and the same holds true for the man who wears one.