Rolex Sea-Dweller Ref. 1665 "Great White" Mk.IV, 1979

This stunning Rolex Sea-Dweller Ref. 1665 “Great White” Mk.IV, 1979 is an exceptional collector’s piece. Its dial is exquisitely aged, the case is sharp and the tritium lume has an even, creamy tone.

The history behind the Sea-Dweller

The Sea-Dweller was developed due to the need for a durable watch that could withstand saturation diving and go deeper than the Submariner watch. The Submariner, launched in 1954, was the quintessential dive watch – reaching depths of 200 metres (660 feet) – but it had an unusual flaw.  

SeaLab expeditions were conducted by the US Navy to test the long-term effects of living underwater in isolation. This naturally meant saturation diving had to be used, which includes helium in the mixture of breathing gas.

The SeaLab divers, wearing Submariners at the time, noticed that the plexiglass would be expelled from the watch during decompression. This was caused by the build-up of helium particles in the case, which had no way to escape during decompression and were forced out through the watch’s weakest point — the plexiglass.

Named after the divers’ long stays underwater, the Sea-Dweller was developed as a solution to this issue. An escape valve for the helium was incorporated into the side of the case so the plexiglass no longer popped out during decompression. The Sea-Dweller was also developed to tolerate more extreme depths than the Submariner.

The reference 1665 was the first reference for the Sea-Dweller – reference 1665 “Double Red” – and the “Great White” retained this reference from its predecessor.

Why the “Great White” moniker?

Having been popular for over 50 years, the Sea-Dweller has been known by various monikers. From 1977 to 1983, the “Great White” followed its predecessor — the “Double Red”. The ‘double red’ in its title referred to the two lines of red text on the watch face. When you look at this Rolex Sea-Dweller reference 1665 “Great White”, you’ll notice that the text is white, hence its nickname.  

What’s special about this “Great White” Sea-Dweller?

This “Great White” Sea-Dweller, circa 1979, offers water resistance up to 610 metres (2,000 feet) and you can see the helium escape valve on the side of the clean and sharp 40 mm case.

A notable feature of the “Great White” is that it was the last Sea-Dweller to include a plexiglass crystal. Many collectors consider the plexiglass crystal to be an essential element of a vintage watch.

The dial on this mark IV watch is in excellent condition — as is the 1570 calibre, which has just had a full service. This magnificent Rolex Sea-Dweller “Great White” also features a period-correct Oyster bracelet, reference 93150 which will fit wrists upto 18cm.