Rolex Double Red Sea Dweller with the
Patent Pending Caseback by Delgado
Rolex Sea-Dweller was developed in close collaboration with the French deep sea
diving company COMEX. Their divers required a timing instrument that could
withstand their working depths, plus be able to remain intact in ascent and
decompression. Most of the watches manufactured at that time could not tolerate
the extreme depths. Helium gas would build up inside the case and at
decompression the gas pressure would increase. The rising inner pressure would
eventually be released by breaking the crystal, the weakest point in the case
Rolex first developed the helium release valve in the 1960s and incorporated it
into some of their Submariner watches delivered to the French diving company,
COMEX. The testing of these specially adapted Submariner 5513 models was so
successful that Rolex specifically made a batch of watches for COMEX and the
watch was given an official model number, 5514. This was such a success that
Rolex decided to market the watch as model number 1665 by 1967.
The 1665 was initially rushed to production and some state that about 114 early
watches were sent to dealers for promotion or early sales. Some authorities
state that the number is less, about 50, while others argue that the number is
much larger and that several hundred may have been made.
The helium valve had been developed and the patent had been applied, but Rolex
had not received final approval. Therefore, the engraving on the caseback of
these early sea dwellers stated in parenthesis “Patent Pending.”
Regular production of the double red sea dwellers started in 1971 and ended in
There were some characteristics on these watches that made
them different from the regular production of double red sea dwellers.
NOTE: You might have noticed that the print of
"Sea-Dweller, Submariner 2000" appears as white, but in reality, the red has
faded to a very light pink which the photograph failed to capture.. Here is a
First, the case was much thinner than the regular
They all had a small helium valve at the 9 o’clock
Marked with the model number 1665
Marked with serial 1.7 million to 2.2 million
The caseback had the Rolex coronet and under “ROLEX” across
the back and not circularly around the caseback.
The following was also engraved “Oyster Gas Escape Valve”
and in parenthesis “Patent Pending”
Inside the Caseback.
The inside of the caseback showed the usual Rolex markings
with the model number, 1665.
The last three digits of the serial are engraved inside.
Lastly, the quarter and year of production of the caseback
is engraved. Most state “IV 67” indicating the fourth quarter of 1967.
Crown and tube.
The crown was a triplock without the external rubber “O”
ring in the tube. The coronet in the crown did not have a line or dots under it
as the current triplock.
The crystal is a acrylic crystal with a high dome.
The dial is a black matt with white indices and plots. The
coronet had a “flat” bottom and the “L” of Rolex lined up perfectly under it.
The words “Sea-Dweller” and “Submariner 2000” in red
possibly printed directly on the dial or over white paint? The print is clear
and easily demarcated. The font is the same for both lines as opposed to the
later dials that used a smaller font for “Submariner 2000”.
Most of these dials, the red print has faded to a light
pink or almost yellow. Therefore, the double pink or double yellow dials.
The depth markings of “2000ft=610m” sans sheriff.
Small markings in the dial for “Swiss – T < 25” indicating
a tritium dial.
The bracelet is a Rolex Oyster 9315 with folded links and
380 end pieces. About thirteen links should be present. The extension of the
bracelet may state “patent pending”.
Box and Papers and other documentation.
As any other watch, these sea dwellers were sold with inner
and outer boxes.
The green tags with the model number in one side and the
full serial number is in the other side.
Rolex Booklet with full serial.
Rolex certified chronometer tag.
This particular watch came with a very interesting letter
from its original owner detailing its history for over its initial 34 yrs.. A
pretty unique watch!
I don’t know how many of the original Patent Pending
Sea-Dwellers have survived but those in this condition and this provenance are
probably few and far between.
In all and from my experience, the PPDRSD is trully a very rare watch. In my estimation, there were less than a few hundred examples ever made. Those samples run in at least two distintive batches (ie close serial numbers). And the mark I dial, is the only dial associated solely with the PPDRSD.