
The markings on the Rolex Crown (winder) signify two different properties of the watch, the crown type, and the metal the watch is made from.
A line, 2 dots, or a single dot underneath the Rolex brand symbol tell us we have a Rolex twinlock crown (water resistant to 100m).
The Rolex triplock crown is represented by 3 dots underneath the Rolex brand symbol and signifies water resistance to a rating of.
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