Philadelphia, PA, United States
This vintage Rolex Sea-Dweller with the 16660 reference number – also known as the "Triple Six" – belongs to the first series of Sea-Dweller watches where Rolex started using sapphire crystal to protect the dial. Nowadays, sapphire crystal is standard across all Rolex watches, however, what separates this particular model is the lack of the Cyclops lens above the date window – making this watch a very special and appreciated piece.
Another upgrade from this Sea-Dweller’s predecessor is improved water resistance – increased from the previous 610 to 1,220 meters (4,000 ft). Being intended for divers, the watch features a gas escape valve. This valve allows the helium trapped in the watch while underwater to be released at a given pressure during decompression, while preserving the case's waterproofness. The gas escape valve is a patented Rolex innovation that was introduced with the Sea-Dweller series in the late 1960s. It resolved an ongoing issue that diver’s watches had at the time, where the crystal would often pop out in the decompression chamber after a dive – a result of helium particles accumulating within the case. By letting the helium particles escape through a controlled mechanism, the issue was solved.
An additional feature that was applied to this Sea-Dweller model was a unidirectional bezel instead of a bi-directional one – making the watch much safer for divers. The bezel sits atop of a 40 mm stainless steel case that is mounted onto a stainless steel Oyster bracelet. This timepiece is equipped with the 3035 self-winding movement that builds up power reserve of 50 hours. Introduced in one of the early batches within the 16660 series, the watch is offered with a black dial that boasts painted circular indexes without surrounds. The dial features central hours, minutes and seconds, and date indication.
The watch is offered in a pre-owned condition and includes a gift box.