Rolex 5514 , the last one !!!!!

5514 = 5513 + valve

Une petite explication en anglais de la 5514 :

The Rolex reference 5514 Submariner, is the iconic COMEX watch; made only for COMEX, it was never available for retail sale and vies with the British Military model 5517 as the most desirable Submariner variant ever made. In the 1960s COMEX pioneered the use of saturation diving in the commercial field; this is a method where divers work at depth and then return to a compression chamber where the atmospheric pressure inside is kept at their working depth. This means that they do not have to go through lengthy decompression at the end of each dive, rather they only have to decompress once, at the end of the session (usually after several days). In order to avoid nitrogen narcosis (the bends) they breathe a mixture of oxygen & helium both in the chamber and whilst working. A problem first encountered by divers was that the extremely small molecules of helium were able to force their way past the watch seals and so the pressure inside the watch would equalise with that in the chamber. However at the end of the session, the pressure in the chamber would be reduced at a rate quicker than the helium could escape from the watch. This meant that the pressure inside the watch was higher than that in the chamber; this pressure imbalance often resulted in the crystal being forced out of the watch at high speed. It was to solve this rare occurrence that Rolex invented the helium escape valve, which enabled the pressure inside & outside the watch always to be equal. These valves were first fitted to a small series of 5513 watches for COMEX & once their efficacy had been proved, a COMEX specific watch was then ordered; the 5514.