Rolex has quite a singular definition of waterproofness.
To Rolex, the airtight quality of its watches exemplifies the expertise ingrained in its entire manufacturing process, from design to final assembly and testing. Since the creation in 1926 of the Oyster case, the world’s first waterproof case, multiple innovations have honed this hallmark, among them, the Twinlock and Triplock winding crowns, helium escape valve and Ringlock system.
The incomparable hermeticity of the Rolex timepiece is the result of the diligence with which Rolex does everything, perpetually.
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Seal the Deal - Rolex and its continued mastery of waterproof watches
In the world of waterproof watchmaking, Rolex remains peerless. The Swiss watch manufacture created the world’s first waterproof wristwatch almost a century ago, and has continued to cement its unmatched reputation by creating over the years underwater horological innovations...: Read Story