The Deep Sea Special Edition is almost unwearable because of its enormous 35 mm thickness and the hemispherical crystal above the dial. The s
econd version is much smaller. It is based on the innovative case construction introduced in 2008 for the mass-produced Deepsea model, which has a pressure-resistant depth of 3,900 meters. Rolex has also fixed some smaller details. The distance between the case and the bezel has been reduced, which limits the amount of dirt that can penetrate the replica watch. The circular luminous markers on the bezel are also not as high and therefore less susceptible to damage. The strap has been redesigned to be softer and more comfortable.
Producing a watch that is extremely resistant to pressure is not really very difficult. The thickness of the case walls and the external dimensions could be increased to the point where a watch with very high water resistance could be made. But Rolex did not go about solving this problem in this way. From the very beginning, the goal of the engineers at Deepsea was to create a wearable watch. They found success using a watch with a diameter of 44 mm and a thickness of 18 mm that was very comfortable to wear.
This required a completely new redesign of the case construction – resulting in the “ring lock system” developed and patented by Rolex. The system consists of three pressure-absorbing elements: a 5.5 mm thick sapphire crystal, a 3.28 mm thick grade 5 titanium case back, and a Biodur 108 steel inner ring. The system is surrounded by a replica Rolex 904L steel case. These materials have been carefully selected for their extreme robustness and resilience so that they will not deform or break under pressure.
The advantage for divers is that water absorbs long-wave light better than short-wave light, so blue light is the easiest to see underwater. How does this benefit the wearer? Impact resistance and reliability are improved. The winding mechanism is more efficient and builds up power reserves faster, largely due to the new ball-bearing oscillator. Most importantly, the maximum power reserve has been increased from the standard 48 hours to 70 hours. Rolex has increased the efficiency of the Swiss lever escapement by 15% through the use of thinner barrel walls, allowing for a longer mainspring, and the innovative Chronergy escapement. This was achieved by modifying the geometry and reducing the weight of the skeletonized shape. The lighter escapement is also noted for its quieter ticking sound.