This is a watch you can safely wear to the very bottom of the ocean floor.

 

In the foreword of a book by oceanographer Jacques Piccard called "Seven Miles Down", Robert S. Dietz recalls how he felt as if he were inside a giant Swiss watch, surrounded by all the many instruments and controls in the bathyscaphe "Trieste".

 

In January 1960, Piccard took a watch with him to the very bottom of an oceanic trench, famous for being the deepest on Earth. It was a special Rolex model.

 

At a time when other watchmakers were looking to explore space, Rolex was deep diving. Rolex actually took two dives into the Mariana Trench — first in 1960 and again in 2012 on a deep-diving submersible called the Deepsea Challenger with James Cameron.

In October 2022, the date of these two historic dives appeared on the caseback of the Deepsea Challenge watch. This watch is an extension of the experimental watch that accompanied Cameron.

 

The only difference is now it's suitable for everyday wear. Its main specs are still the same: waterproofness to a depth of 11,000 meters (it's actually endured a test pressure equivalent of 13,750 m in an ultra-high-pressure tank), although many details have changed to make the watch suitable for wristwear.

 

The 50-mm case is made of a titanium alloy called RLX, which has allowed the watch to be made 30 % lighter. The glass has become flat and thinner. Its unbelievable level of waterproofness is maintained by the case's patented Ringlock system and indispensable helium escape valve.

 

Rolex Deepsea Challenge
Rolex Deepsea Challenge

Ringlock appeared as a result of improvements made to the Oyster case: a change of the case's structure, adding thick sapphire glass, a caseback made of RLX titanium and a compression ring made of nitrogen-alloyed steel.

 

The winding crown is protected by the Triplock triple-seal system, first introduced back in 1970. The watch is equipped with the Perpetual 3230 movement that debuted in 2020.

 

It uses the patented Chronergy escapement with an escape wheel made of a nickel-phosphorus alloy, an optimized Parachrom hairspring with a Rolex overcoil and 70 hours of power reserve.

It's a COSC-certified chronograph movement with Superlative Chronometer certification, as its specs transcend the standards that must be met to receive certification from the Official Swiss Chronometer Testing Institute: average timekeeping gains and losses are –2 /+2 seconds per day.