This OMEGA is certainly a piece of history, but there are many things about it that have been said incorrectly and have helped to define a history over the years that does not entirely belong to it.

Let's start with the name.

The real name of this very particular timepiece is Omega SEAMASTER 600 " Plongeur Professionnel", or Professional Diver, the abbreviation "PLOprof" was attributed to it by collectors, and more precisely from a description that appeared in a monographic book that illustrated its characteristics.

Another incorrect attribution was the year of marketing, it is believed that the first watches arrived on the market in 1970, instead more in-depth studies confirmed that the Ploprof made its appearance on the market in the second half of 1971, from '68 prototyping and experimentation activities started.

It is said that the great Jacques Cousteau participated in the creation of the watch, providing his technical contribution. FALSE.


Cousteau used the watch, already in production, for some of his experiments on the body and human psychology while diving, but there is no record that can confirm that he was part of the design of the timepiece.

How was Ploprof actually born? Let's start from the beginning..

On October 3, 1961, one of the most important companies in the field of deep-sea diving, Comex, was born. It was founded in Marseille by Henri Germain Delauze, a professional diver, record holder in diving as well as a geology graduate. The company soon became a leader in the diving market on offshore oil platforms, in the field of maintenance and installation of submerged components.

Professional scuba divers took great risks working below the surface of the sea and a fully reliable and durable wristwatch that could tolerate the enormous water pressure at such depths without losing accuracy was a vital and indispensable tool for this type. by profession. Delauze said: "A half-hour dive to 350 meters cannot last 31 minutes but 29 minutes and 59 seconds."

In 1968, COMEX asked Omega to produce a watch that it was capable of withstand depths exceeding 400m, as many of you know, the biggest problem, in addition to the pressure exerted by the water at great depths, was the helium used in the hyperbaric chambers, the gas seeping into the watch blew its glass apart. There is no evidence that these leaks may have occurred with some Ploprof specimens, but a statement from the American diving research center Ocean Systems Inc., certified the Ploprof as a watch with a higher water resistance than a submarine.

In addition to field tests, numerous laboratory tests were carried out, in which the case was subjected to a continuous hydrostatic pressure of 60 ATM. In other cases the watch was brought to a depth of 1370m which decreed its arrest, but only because the glass underwent a deformation in the central point, and, resting on the second hand, stopped the running of the watch. This test showed that the components that made up the Ploprof had a greater tolerance to the depth (more than double) reported on the dial (600m).


The main feature of the Ploporf, absolutely innovative for the watches of the time, was certainly the conformation of the case, in monobloc, or obtained by digging a steel ingot from solid. Work certainly very expensive for the time. Another unusual feature for a diving watch of those years was the blocking of the bi-directional bezel, in fact, it could only be adjusted by pressing the red button positioned in the so-called upper part of the case, this guaranteed safety against accidental movement.

An interesting curiosity is to note how the watch seems to be left-handed, having the crown on the left, in reality, the position of the latter arises from the need to protect the most "delicate" part of the watch from involuntary manipulation and guarantee greater comfort in the diver's movements during diving.

There is a version made for left-handed people, but due to assembly errors it was withdrawn from production as it was impossible to maneuver, in fact the crown release button was positioned in the lower left part, making it impossible to release it using only one hand.

Another Omega innovation featured on this watch was the crown locking mechanism. The crown itself, which at first glance would appear to be the sprocket, is actually the square end plate. The sprocket is instead a locking nut. The Ploprof had the most effective crown protection and sealing system ever designed, only the Panerai crown comes close to these design features. The locking nut patent (number CH503310) was filed on October 23, 1968 but not published until 1974.

Only 5 models are known to exist in the world that have a red knurled crown. The reason lies in Omega's choice to replace the classic steel crown with a red plastic crown, this to prevent divers, regardless of the damage that the salt air would have caused to the toothed steel parts if they had not rinsed well, they could damage the watch. It was soon discovered that the plastic material was much weaker than steel, so the manufacturer reverted to the old alloy.

Even the dials during production have undergone several changes.

Nine different types of dials have been catalogued , some have different colours, obtained with the use of particular pigments, which then caused deterioration, modifying their appearance. Others have different graphics, starting with the first, which never ended up in the classic commercial channels, which featured only the Seamaster writing.

In Italy the Ploprof owes part of its fame to one of the most famous wrists in the world, we are talking about the Avvocato wrist.

Many attribute Agnelli's extravagant habit of wearing his watch to a reason for the correct conservation of his shirt cuffs, others only to a way of getting noticed, or even those who say he wanted to save time and read the time faster, the the most plausible and confirmed explanation is that the lawyer suffered from an allergy to some metals, which in contact with the skin caused irritation, which is why he wore the watches over his cuffs.

The Ploprof, thus on display, certainly benefited from it.

We hope that your knowledge of this particular model has been enriched with other details that you may not have known. the next article