The History of the Ring Lock System
The Sea-Dweller and Submariner have been Rolex’s dive watches for over four decades. While the Submariner remains a mainstay of the brand’s lineup, the Sea-reign Dweller’s came to an end in 2008. It gave birth to a brand-new model with even more robust capabilities: the Deepsea. The Deepsea is similar to the Sea-Dweller in several ways. It has a unidirectional rotating bezel with 60-minute graduations and Rolex’s patented helium escape valve. However, Rolex developed another one-of-a-kind patent with the Deepsea, giving it incredible capabilities: the Ringlock system.
How Does It Operate?

The Ringlock system is comprised of a single compression ring located between the dial and the crystal. What makes this ring so special and capable is its construction. Rolex uses a nitrogen-alloyed steel called BioDur 108, which is three times as strong as traditional stainless steel. As a diver descends to greater depths, the pressure increases on the crystal and caseback. This is because they make up the most surface area of the watch. For this reason, Rolex uses a thick, 5.5mm domed sapphire crystal coupled with a unique caseback consisting of two parts. Here, the brand employs a flexible, Grade 5 titanium alloy for the inner back. Then, they use their traditional Oystersteel for the outer screw-down caseback. The titanium alloy allows the back to be more flexible under pressure without cracking or becoming deformed. Still, it’s not enough. This is where the Ringlock system comes into play. Its makeup along with its strategic positioning allows it to take on that pressure as the crystal and caseback press together. Ultimately, it almost completely minimizes any strain on the watch case and important internal mechanisms.
Ring Lock System Capabilities

The Deepsea can boast staggering depth ratings thanks to this innovative system. While the Sea-Dweller could only reach depths of around 1300 metres, the Deepsea can reach three times that. The civilian Deepsea can withstand water depths of up to 3900 metres. However, the model’s technology is scalable, and Rolex has created a special variant with even more impressive capabilities. The Deepsea Challenge watch was created in 2012 in collaboration with the legendary James Cameron. Cameron put the model to the test as he descended to the Mariana Trench, the deepest point in the ocean. He went 10,908 metres below the surface here. This feat enabled the Deepsea Challenge to successfully set the record for the deepest dive for a wristwatch. The civilian Deepsea, by comparison, is 44mm wide and 17.7mm thick. The Deepsea Challenge, on the other hand, is 51.4mm wide and 28.5mm thick, with a sapphire crystal that is over 14mm thick. Even for the most experienced amateur or professional diver, the Deepsea Challenge is not a practical watch. Still, Rolex’s ability to scale this remarkable technology in this manner demonstrates that the sky (or rather the sea) is the limit.