Rolex is no stranger to niche models, specifically ones that specialise in less-than-mainstream purposes. The Milgauss, for example, was designed for scientists at CERN in the 1950s to withstand magnetic fields up to 1,000 gauss. Outside of this rather limited environment, it didn’t have much consumer appeal until its much later years and final models (now discontinued). The Sea-Dweller is an interesting one as it debuted well after the king of dive Rolex replica watches for sale, the Rolex Submariner. That one had a design standard and cool factor good enough for James Bond, so why was a separate dive model even considered? Well, the Sea-Dweller solved two common problems for saturation divers in the 1960s – high-pressure water intrusion and crystals popping off during decompression. The original Submariner had an impressive depth rating (at the time) of 200 metres that ultimately increased to 300 metres, but the Sea-Dweller doubled that with an initial depth rating of 610 metres.
Saturation Diving
Saturation diving was never a mainstream activity and involves long stretches of time at extreme depths, often weeks. These divers are literally deep-sea dwellers, hence the name, and only need to decompress at the end of long-term dives. Underwater construction projects or specialised research are common necessities for saturation diving, which can reach depths below 300 metres (701 metres is the record). Divers first descend in a pressurised chamber and breathe a mixture of helium and oxygen to prevent dangerous nitrogen buildups (nitrogen narcosis) and acclimate to the deep-water environment. They can then work at depth for extended periods without needing to resurface and decompress, living in deep pressurised chambers between water excursions. Only at the end of the mission do they finally decompress.
Helium has a very small molecular size and can penetrate UK AAA Rolex fake watches during the descent as divers are surrounded by the oxygen/helium mixture. During decompression, the helium expands within the watch and builds internal pressure. Without a specific method of escape, it will find the weakest point of the watch – where the crystal meets the case – and often pop it off like an overfilled balloon popping. Just like the Milgauss was designed for scientists working around strong magnetic fields, the Sea-Dweller was designed for saturation divers working at extreme depths in an oxygen/helium environment. Niche yet necessary, as the popped Submariner crystals would attest.
1966-1967 – Sea-Dweller 1665 Prototypes – The ‘Single Red’ Models
Before the production 1:1 quality Rolex Sea-Dweller replica watches debuted in 1967, there were experimental Sea Dwellers known as the Single Red models, or SRSD. SEA-DWELLER was printed in red without a second red line underneath – SUBMARINER 2000 – as seen on the production “Double Red” ref. 1665. This second depth line was instead printed in white and SUBMARINER 500 M – 1650 FT (not 2,000 feet like the production model). These early prototypes had the general formula established with a classic black, bidirectional rotating diving bezel with a detailed 15-minute scale, large tritium indices identified by SWISS – T < 25 printed just above 6 o’clock, Mercedes hands and a date window at 3 o’clock. The date was considered necessary as saturation divers spent weeks underwater and needed to keep track of the days. No prototype had a cyclops lens over the date (it only appeared on the most recent models from 2017). Approximately 12 examples of the Single Red Sea-Dweller are known.
The famous Rolex coronet was printed in white with ROLEX and OYSTER PERPETUAL DATE printed underneath, and all were certified chronometers. Many prototypes didn’t have a helium escape valve, so although the depth rating was higher than the Submariner, the expanding helium was still a potential issue. All early prototypes are extremely rare today and only a relative handful were designated for the U.S. Navy SEALAB 3 Aquanauts that descended beyond the technical capabilities of the Submariner. Oceanographic Consultant for Rolex, T. Walker Lloyd, personally chose the professional divers to test them.
Prototype #1820177 was the first to feature a gas escape valve and belonged to Dr. Ralph Brauer, a renowned hyperbaric researcher who achieved depth records in the late 1960s and studied High-Pressure Nervous Syndrome that can happen below 1,000 feet. There are other prototypes known to have gas escape valves as well, which became standard on the first production model. These prototypes had escape valve engravings on the case back and “Patent Pending,” which differed from production Rolex copy watches for men with “Rolex Patent.” However, very early production models had “Patent Pending” as well in 1967.
Helium Escape Valve
The solution to expanding helium in dive watches was a one-way gas escape valve on the case side, or more specifically, the helium escape valve. Bob Barth was a saturation diving pioneer in the 1950s and 1960s and a former US Navy Aquanaut, and he conceptualised the use of these escape valves to prevent crystals from popping off, which was embraced by Rolex engineers.
Rolex was first to file the patent for the helium escape valve (Swiss patent CH492246), which has since become a standard for many dive Rolex replica watches UK wholesale with high depth ratings. There is currently some discussion amongst watch historians regarding the invention of the HEV, as Doxa could be the company that first developed this device.
In the same era, Omega went in a different direction, also in partnership with French diving company Comex (Compagnie Martime d’Expertises), and developed a case so robust and airtight that helium couldn’t enter in the first place – the PloProf Research Program. With the helium escape valve, Rolex could use its standard Oyster Case without radical modifications for extreme depths.
1967-1977 – The First Production Sea-Dweller, the ‘Double Red’ Ref. 1665
As the name suggests (and mentioned above), the Swiss movements fake Rolex Double Red Sea-Dweller or DRSD watches had a second red line printed under SEA-DWELLER on a matte black dial that established its 2,000ft or 610m depth rating with SUBMARINER 2000. Underneath that, in bold white print, was 2000ft = 610m to hammer the point home. The overall aesthetic was otherwise the same as the escape valve prototypes, with the aluminum black rotating diver’s bezel (still bidirectional with a lume pearl), Mercedes hands, large painted tritium indices, printed coronet, ROLEX and OYSTER PERPETUAL DATE, along with a date window at 3 o’clock without a cyclops lens. Prototypes and Ref. 1665 also shared the same pointed-style crown guards. Unlike early Submariners, there was never a Sea-Dweller with a coveted gilt dial.
The 40mm stainless steel case was similar in appearance to the Submariner, but the helium escape valve at 9 o’clock was the easy visual differentiator, along with the date window that early Submariners lacked until 1969 (and those came with a cyclops lens). Ref. 1665 crystals were thick, domed acrylic, and the cyclops lens on early Submariners was simply glued on and not integrated, which wouldn’t withstand the extreme depths of saturation diving.
There were minor dial print variances within the cheap super clone Rolex Double Red Sea-Dweller ref. 1665 series watches, designated by Mark 0, 1, 2, 3 or 4 dials. Later replacement dials from Rolex had even more differences with Mark 5, 6 and 7 dials. These variances were likely ignored back in the day, but are a big deal for collectors now. The Ref. 1665 designation was still used from 1977 to 1983, but those no longer had Double Red dials and are known as the “Great White” models with all white print.
1977-1983 – The Sea-Dweller ‘Great White’ Ref. 1665
As this still falls within ref. 1665, not much has changed other than all white print on the matte black dial, although SUBMARINER 2000 was removed. As is often the case with Rolex, particularly in earlier eras like this, there are a host of minor dial variances that collectors seek out today (Mark 0 through Mark 4 dials here). A notable variant is the Great White rail dial (seen on Mark 2 dials), where the C on CHRONOMETER lines up with the C on CERTIFIED underneath.
If you look closely, you’ll also see that the minute track has longer marks on rail dials and the tritium indices are just a hair closer to them. The tritium reference at the bottom is also different, T SWISS T < 25 instead of the standard SWISS – T < 25. Again, no one really cared at the time, but collectors certainly care today. The Great White ref. 1665 was also the last luxury Rolex Sea-Dweller replica watches UK with an acrylic crystal.
1977-1981 – The Comex Sea-Dweller Ref. 1665
French commercial diving company Comex (Compagnie Maritime d’Expertises) worked with Omega as mentioned above, but also had a fleet of saturation divers that were issued Sea-Dwellers. These were special editions that differed from consumer models, which are easily identifiable with COMEX printed in reverse (black letters within a white background) that replaced SEA-DWELLER on the 1665 dial. Comex 1665 dials were also Great White rail dials, but the depth rating was curiously listed as 600m instead of 610m (still 2,000 ft). The coronet was also a bit shorter on these Comex dials, and the tritium designation was that of non-rail dial models, SWISS – T < 25. DATE was removed from OYSTER PERPETUAL on the line just under ROLEX, although it was still a date model. Only 300 Comex 1665 models left the factory, so they’re highly collectable today.
Top fake Rolex Comex Sea-Dweller watches were made over a 20-year period, starting with ref. 1665 from 1977 to 1981, then ref. 16660 from 1980 to 1984 and ref. 16600 from 1992 to 1997. There was an eight-year gap between 1984 and 1992. All Comex models had the issue number engraved on the outer case back. This just covers the professional diver models and not gifts or awards that were also produced.
Calibre 1575 (for all 1665 variants)
This is the date variant of calibre 1570, first manufactured in 1965, and you’ll most likely see “1570” engraved on 1575 movements. It’s just a Rolex thing, but obviously, the date complication makes it easy to differentiate the two. A GMT variant was also made for the Explorer II and GMT-Master in the 1970s. 1575 movements did not feature a quickset date, so the hands had to be spun to eternity if significant changes were needed, but that was a common inconvenience at the time. However, the cam and jewel system allowed for an immediate change at midnight. It had 25 jewels, beat at 19,800vph (2.75Hz) and had a 42-hour power reserve, and all were certified chronometers.
1978-1989 – Sea-Dweller ‘Triple Six’ Ref. 16660
This next reference was a rather sizeable leap from all ref. 1665 models and represented a more modern and mature Sea-Dweller. For starters, it switched to sapphire crystals from acrylic and is only the second perfect copy Rolex watches to do this (the Day-Date beat the Sea-Dweller by about a year). The case remained 40mm in diameter, but was noticeably thicker and heavier, which allowed for double the water resistance – from 2,000 feet to 4,000 feet or 1,220 metres. Overkill? Perhaps, but also a real engineering achievement. With the higher depth rating came a larger and more robust helium escape valve, along with the latest Triplock crown with three O-ring gaskets (first used in 1970 and debuting on the Sea-Dweller). The rotating bezel also went from bidirectional to unidirectional, which is more of a professional standard to eliminate accidental “back turns.”
Dial changes included a switch from matte to glossy black, although early models retained the matte dial with painted tritium indices. As production went on, the switch was made to glossy black with applied white gold indices with tritium inserts. This brought the Sea-Dweller into the modern age as matte dials with painted indices have a much more vintage aesthetic. For collectors, the early matte dials are more desirable than the newer glossy counterparts. The date window background also switched from light silver to white, which was standard for the new calibre 3035 (see below).
From 1980 to 1984, Rolex produced 200 Comex 16660 Sea-Dwellers that were technically the same as the consumer 16660, with visual differences. DATE was once again printed after OYSTER PERPETUAL (removed on Comex 1665 dials), and SEA-DWELLER was back on the dial, this time printed underneath the depth rating, while COMEX was printed above the depth rating. Well, this was the format for the first 100 with matte dials, while the second 100 with the newer glossy dials and white gold indices had more dial print with SUPERLATIVE CHRONOMETER OFFICIALLY CERTIFIED, adding two additional lines.
All ref. 16660 models had an improved movement over the workhorse 1575, which added the convenience of a quick-set date function and a higher beat rate of 28,800vph (4Hz). Introduced in 1977, it had two more jewels at 27, but the same 42-hour power reserve. Not all 3035 movements were certified chronometers, but all inside Swiss made Rolex Sea-Dweller replica watches were, and the calibre was used in the Datejust, Submariner and Date as well. It’s notable that the hairspring was held with glue, as the next calibre utilised more advanced and secure laser welding.
1989-2009 – Sea-Dweller Ref. 16600, Simple Refinement
This reference was nigh identical in appearance to the glossy dial “Triple Six” models, but small refinements added up. Did the water resistance change? No, it remained at 1,220 metres. New dial elements? Those (mostly) stayed the same, although a relatively unnoticeable change was the evolution of lume. Tritium remained in early models with T SWISS T < 25 at the bottom of the dial, while Luminova replaced it in 1998 with only SWISS at the bottom. Luminova was actually a Japanese lume produced by Nemoto and Co., so in 2000 Rolex switched again to Super-LumiNova, the very popular Swiss-made lume and SWISS MADE was printed at the bottom.
These three designations at the bottom of the dial help determine both the timeframe of production and type of lume used. Although cheap UK Rolex replica watches‘ in-house Chromalight was introduced in 2008, the last ref. 16600 models still used Super-LumiNova. Ref. 16600 may have been a somewhat boring update in the Sea-Dweller line, but it had the longest production run of 20 years. As a result, this is a good value proposition for those looking for a modern Sea-Dweller without breaking the bank or needing collectable street cred. An honest deep-sea tool watch, and among the best dive watches by any measure.
1992-1997 – Comex Sea-Dweller Ref. 16600
Comex models returned after an eight-year absence in 1992 with another 200 models. These were again delivered in two batches and five years apart – the first 100 in 1992 and the second 100 in 1997. These were also the last “professional” Comex models produced by Rolex. All dials had tritium and both batches were visually identical, but the case back engravings differed. The first 100 case backs had ROLEX and COMEX in straight lines in the centre, while the second 100 had ROLEX and COMEX curved around the perimeter. The 1,220m depth rating and helium escape valve were identical to the consumer ref. 16600 models.
Calibre 3135
All best quality fake Rolex ref. 16600 Sea-Dweller watches had the updated calibre 3135. The jewel count increased from 27 to 31, the power reserve increased from 42 hours to 50 hours and the hairspring was now secured via laser welding instead of glue. A balance bridge also replaced the balance cock. Interestingly, setting the time with the crown changed from counterclockwise on the 3035 to clockwise on the 3135, although there’s no real advantage either way. Both movements beat at 4Hz and had Microstella regulation. It was a nice technical improvement, but bigger and better things were on the horizon.
2008-2017 – The ‘Deepsea’ Sea-Dweller Ref. 116660
This evolution of sorts (almost a different model entirely) represented another big leap in the series, not unlike the jump from ref. 1665 to 16660 with the water resistance rating doubling from 610 metres to 1,220 metres. The China 2025 replica Rolex Deepsea variant of ref. 116660 watches goes from 1,220 metres to 3,990 metres, more than tripling the depth rating this time. Kind of a moot point as the deepest saturation dive topped out at 701 metres, but it’s still an amazing technical achievement. For starters, the sapphire crystal was a full 5mm thick (thicker than many ultra-thin watches with crystal) and the new, patented Ring Lock System was a major addition.
A ring of hardened nitrogen alloy steel (BioDur 108) internally supported the crystal and Grade 5 titanium case back (removing stress from the case itself) and is visible and clearly marked just inside the rotating bezel. The case back was actually a two-part design with a titanium central back and outer 904L stainless steel screw-down ring, which helped redistribute pressure back to the Ring Lock System. The case itself grew to a sizeable 44mm in diameter and 17.7mm in height to accommodate the massive pressure increase and the bezel insert was now ceramic Cerachrom instead of aluminum. Rolex’s in-house Chromalight also replaced Super-LumiNova. DEEPSEA was printed in white under OYSTER PERPETUAL DATE below 12 o’clock and the whole package weighed in at 7.5 oz or 212 g. With the larger case came oversized indices and larger hands for a Maxi dial, changing the overall look from the prior ref. 16600. The Oyster bracelet featured both the Glidelock System for 20mm of extension without tools and the Fliplock extension link, allowing for an additional 26mm of extension via three folding blades.
This became a standard Sea Dweller option and addition to the normal range, but there was also a five-year pause for the new (regular) 40mm ref. 116600, which didn’t appear until 2014. So, not an absence like the Air King or Milgauss, which both disappeared completely and then reappeared years later, but you were limited to the Deepsea Sea-Dweller variant for a few years.
2014-2017 – The Return of the SD4000, the Sea-Dweller Ref. 116600
Forgetting about the Deepsea variants for a second, this technically follows the 40mm ref. 16600, last seen in 2009. Although the Rolex Deepsea fake watches shop were upgraded with Chromalight and ceramic Cerachrom bezel inserts prior to this, those upgrades were a big part of what made this model “new”. This was also updated with a Maxi dial and the bezel had a more detailed 60-minute track instead of just 15 minutes. The clasp was upgraded to the Glidelock System as well, but the depth rating remained the same – not that it needed to improve from 1,220 metres. It was still powered by calibre 3135, which was more than adequate if not a bit long in the tooth.
Although ref. 116600 brought some nice updates with Chomalight and the Cerachrom bezel insert along with a Maxi dial and more detailed bezel marks, it was very much a transitional model and the shortest-lived of all Sea-Dwellers at only three years.
2017 to Present – Sea-Dweller 43mm Ref. 126600
This, of course, is the most modern Swiss movements Rolex Sea-Dweller replica watches, which was made to celebrate the 50th anniversary of the model, but it also takes a big step forward compared to the ref. 116600. For starters, the case is significantly larger at 43mm in diameter (from 40mm), which helps separate it more from the classic Submariner. And that’s because this is the first Sea-Dweller to feature a cyclops lens over the date window, giving it more of a Submariner vibe. SEA-DWELLER is also printed in red, which is a nod to the early Single Red prototypes in the 1960s before the Double Red production models, ref. 1665.
To accommodate the new case size and provide a more contemporary look, the lug width went from 20mm to 22mm. The 43mm case now stands between the 40mm Submariner, 44mm Deepsea and 50mm Deepsea Challenge, giving serious divers (or more realistically, diving fans) a nice variety that goes with the recent upsizing trend from Rolex. Odds are, you’ll never take any Sea-Dweller even close to its depth capabilities, but knowing it can go that deep is part of the fun. Note that there’s also a Rolesor edition in steel and yellow gold, the reference 126603.
Calibre 3235
Like the Deepsea Challenge from 2022, this Sea-Dweller 43mm gets Rolex’s (almost) latest Chronergy escapement. Compared to the previous calibre 3135, the 3235 brings a new gear train, barrel, bridges, plates, winding system, escapement, Parachrom hairspring and more – about 90% of everything is new. The Chronergy escapement and new architecture bring a Superlative Chronometer rating of +/-2 seconds per day, which is well inside the standard COSC rating of -4/+6 seconds per day. It beats at 28,800vph (4Hz), the general Rolex standard (not mentioning the latest 5Hz calibre 7135 introduced at Watches and Wonders 2025), has 31 jewels and a 70-hour power reserve. This generally represents the best of Rolex engineering, but the aforementioned high-beat calibre 7135 in the 2025 Land-Dweller is the next generation with a new escapement called the Dynapulse. However, I’m sure the Chronergy escapement will live on for many years.
2018 to Present – 2nd Generation Deepsea Sea-Dweller Ref. 126660
Not too much changed aesthetically between ref. 116660 and 126660 Deepsea Sea-Dwellers, but we’ll start with the lug width that went from 21mm to 22mm, necessitating an updated and wider Oyster bracelet. The case diameter of 44mm, however, remains unchanged along with the Maxi Dial layout. The matte black and James Cameron D-Blue Edition dials are also the same. The major change is the upgraded movement, going from calibre 3135 in ref. 116660 to calibre 3235 in the new standard Swiss AAA fake Rolex Sea-Dweller ref. 126600 watches (see above). As mentioned, the 3235 brings the new(er) Chronergy escapement and Superlative Chronometer rating of +/-2 seconds per day.
The Deepsea went even further, going with a full-on 18k yellow gold option with ref. 136668LB. It’s one heavy beast and the ultimate flex if you like that kind of attention… A rather surprising release, which shows the move to luxury rather than professionally-oriented tool watches.
2022 to Present – James Cameron and the Deepsea Challenge Ref. 126067
Rolex formed an unusual partnership with film director and deep-sea explorer James Cameron in 2012, so let’s start with the James Cameron Deepsea edition from 2014 that honoured his 2012 dive to the Mariana Trench at 10,908 metres. Known as the Deepsea D-Blue Edition, it had a gradient blue dial that went to black at the bottom half (to represent the depths of the sea). It was an unusual piece for sure, but not a limited edition and not even the most interesting of the Deepsea collaborations with Cameron. Meet the Deepsea Challenge…
In 2012, the craziest of the crazy Rolex Sea-Dweller replica watches shop UK was attached to the side of Cameron’s submersible and descended all the way to 10,908 metres – and survived. This custom Deepsea Challenge had a huge 51.4mm diameter and was 28.5mm thick (with a 14.3mm sapphire crystal), but a 50mm Grade 5 (RLX) titanium consumer version surfaced in 2022 as ref. 126067, the first all-titanium Rolex. It differed both in size and material from the 2012 prototype, which was 904L stainless steel. The 50mm consumer Deepsea Challenge was 23mm thick with a 9.5mm sapphire crystal (61mm lug-to-lug), but the titanium made it kind-of wearable at 250 grams (compared to around 400 grams).
The matte black 126067 dial had DEEPSEA CHALLENGE printed below OYSTER PERPETUAL (there’s no date window on this piece) and 36090ft = 11000m printed below SEA-DWELLER above 6 o’clock. It featured the Deepsea Ring Lock System and all print was white for a monochromatic, serious dive watch experience. This watch was best worn over a wetsuit as the size and weight quickly became a burden as a “normal” watch, although large wrists and diehard enthusiasts could surely pull it off. It’s powered by the time-only calibre 3230 Superlative Chronometer with Rolex’s latest (at the time) Chronergy escapement and +/-2 seconds per day accuracy rating. It was fitted with a titanium Oyster bracelet and Rolex Glidelock and Fliplock extension systems, because overkill was the name of the game. It’s huge, it’s ridiculous and just super cool.
Collectors
Like all Rolex models with a long history, vintage models tend to command higher prices, but if you can find a recent titanium Deepsea Challenge, it likely won’t be at retail and may approach double the price. That said, the overall market is in a bit of chaos at the moment, so things could certainly change. The most expensive and hardest to find models are the Single Red prototypes, where about a dozen are known to exist. A millionaire might get lucky at an auction if one surfaces. The next hard-to-find models are some Comex editions, which are more realistic to acquire, but if you have to ask about price, it’s probably not for you. These are six-figure Rolex fake watches paypal, although I did find a late one for USD 92,000. Then there are specialities like Tiffany-branded dials and so on that command a premium, but beware of fakes! Due diligence is important here.
For us mere mortals, we can start with the Double Red 1665 models, which start at around USD 25,000 for a nice piece. Later Great White variants can be found for half that price. Nice ref. 16600 models (with a 20-year production run) can be had for around USD 7,000, so these aren’t out of reach by any stretch and are often less expensive than comparable Submariners. A nice James Cameron Deepsea ref. 116660 sells for around USD 11,000. Overall, the Sea-Dweller and Deepsea models are surprisingly attainable on the secondhand market, going all the back to the 1970s. Even a recent Rolesor ref. 126603 can be found in excellent shape for USD 15,000 (it now retails for over USD 19,000). You again won’t find a Deepsea Challenge at retail – it’s just a Rolex thing – so if you want one, be prepared to spend north of USD 40,000, despite it retailing for USD 27,000. For Daytona fans, even that seems somewhat reasonable.
None of the 1:1 online replica Rolex Sea-Dweller watches make a whole lot of sense from a practical standpoint – very few actually dive below 100 metres, and most serious divers use wrist computers today. But they’re cool in a Lamborghini Aventador LP 780-4 Ultimae kind of way. You know what it can do, and that’s cool enough, even when the machine far surpasses the owner’s capabilities. As for me, with my smallish 6 ¼” wrist, I’d go for the Deepsea Challenge if money was no object because I like pushing the boundaries with the absurd. For everyone else looking for a nice daily driver, I recommend a clean ref. 16600 or a more modern 116600 – easy to find, contemporary, and you won’t break the bank too much.