There is a curious obsession among watch collectors. Often, those deeply embedded in the industry will yearn for less typography on a dial to allow the strength of the watch design itself to shine. But in the case of certain timepieces, sometimes those extra few letters or signatures signify a different thing entirely. Something incredibly special and exclusive that takes what otherwise would be a conventional example of a reference down a different path. For a Rolex Submariner' signed with "COMEX", that path is submerged, operating under a professional grade purpose in some of the most challenging conditions on earth.

Co-signed dials have long existed in the world of watchmaking. Initially, the concept was used to signify the intimate relationship between manufacturers and retailers. For many legacy houses such as Rolex, Patek Philippe, Vacheron Constantin, Audemars Piguet, Cartier, Breguet, and so on, the network of retailers was critical in getting watches on clients wrists, and there was no greater way to honour the importance of that relationship than by the brands adding a retailers name to their dial. Beyer, Gübelin, Asprey, and of course, Bucherer (then signed 'Bucherer's) remain some of the most celebrated dual signed watches today, while the Patek Philippe and Tiffany and Co. partnership was thrown into the spotlight in 2021 with the announcement of the modern final reference of the Nautilus 5711 Tiffany Blue.

Other examples of co-signed dials include those ordered as corporate gifts, most famously the Domino's Pizza Air Kings, which Domino's ordered directly from Rolex and gifted to store managers.

For a long time, collectors held the opinion that co-signed dials detracted from the purity of the original concept of the watch in question, but today, the market has matured to embrace their uniqueness. Each co-signed watch represents more of a partnership than a form of collaboration, with the extra signatures adding further provenance, sparking curiosity about the stories the watch could tell if it could talk. But when it comes to pondering bygone lives, few co-signed watches can compete with Rolex and COMEX.

The tale of Rolex's journey underwater is, in many ways, industry-defining, and it's primarily thanks to the Submariner. In 1953, Rolex developed the watch purely as a professional tool for divers. When the piece officially debuted in 1954, it was the first wristwatch to achieve 100 metres of water resistance, setting the benchmark for the numerous dive watches that would subsequently follow in its footsteps. Since its inception the Submariner has evolved to its current luxe status, but it could only achieve this status on the merits of its underwater competence and function.

COMEX ('Compagnie Maritime d'Expertises') is the Rolex of the diving world, specialising in deep-sea diving, underwater engineering such as offshore drilling or subsea infrastructure, and hyperbaric technologies. The work is extremely dangerous and requires immense skill, competence and patience. A reliance on tools that perform without fault is critical to the success of projects, which is why, in 1970, Rolex and COMEX officially began their partnership.

From COMEX's perspective, the arrangement involved receiving Submariner and Sea-Dweller watches for their divers at no cost, while in return, Rolex gained access to performance analysis reports. These special watches also featured something new: a co-development between both companies called helium escape valves. These valves reside on the side of the case and act as pressure release systems to ensure watch crystals won't pop off during deep saturation dives due to internal pressures. These escape valves are still a staple of highly water-resistant watches today.

This partnership between Rolex and COMEX remained in place for 27 years, and across both the Submariner and Sea-Dweller, it's estimated that around 3,000 official COMEX watches were produced. For context, that's an average of approximately 110 watches yearly, staggeringly low numbers for the Coronet. As such, today, they remain one of the most desirable co-signed watches not only by Rolex but in the entirety of watchmaking. Furthermore, one of the most significant sides to their desirability is that they were never made commercially available. Every Rolex COMEX was specifically produced and issued to certified COMEX divers, adding unique provenance and genuine soul to those titans of the diving world that still survive today.