Six generations of the Rolex Sea Dweller...
When I first obtained a Sea Dweller (SD) in 2013, the 16600, the Deep Sea Sea Dweller (DSSD) was Rolex's evolutionary step forward. The original Sea Dweller was no longer in production and that left us with the iconic Submariner / Submariner Date and the new DSSD. I think it's clear that many mourned the "death" of the classic SD, myself included. Well it took Rolex five years to succumb to classic-SD fans by releasing the 116600 or "Sea Dweller 4000" at the 2014 Baselworld. Using the same "upgrade" concept they applied to the Submariner line, the SD now had stockier lugs and crown guards, a Cerachrom bezel and Chromalight lume. It did however keep it's 40mm stature (just as the Submariner lines did). The 116600, aka the "SD4K" immediately attracted those that couldn't justify the DSSD's 44x18mm heft or the addition of the Ringlock system, etc.
For more background on the Sea Dweller and generations, please see my writeup on the 16600 or excerpts from it down below.
click-the-pics for hi-res goodness
...Serving saturation divers for half a Century!
Looking down at my 16600, I knew that it would be nice to some day compliment it with the SD4K but I figured I'd wait for the aftermarket price to drop and assumed it would be in production for years to come. Who would have thought that just a few years later, Rolex would replace the SD4K... ! Well, it happened, at Baselworld 2017, the 116600 was out and the 126600, aka SD43 or SD50 was in! The timing is significant in that the first SDs were released in 1967 (for professional use only), making 2017 the 50th anniversary of the Sea Dweller.
Wait, what ...a cyclops?!?
Full disclosure... the first time I saw the SD50 all I could think of was ...to get my hands on the SD4K! Is that a cyclops?!? What were they thinking? DSSD-sized? Is this an SD or a DSSD replacement.... or both? The realization that the SD4K would now be considered "limited production" made it all the more tempting. So who would have thought I wasn't the only one gunning for one (...lol). There were very few on the market in 2017 and those few were going for considerably above retail. So my attention wandered as there were a few other impressive pieces from Baselworld on my short-list... .
SD4K vs. SD50
A year and a Baselworld later... I was again lusting after a modern SD. I got very lucky in the sense that I had the opportunity to try on both the SD4K and SD50, just days apart. First up was the 116600. Same diameter as the 16600, slightly higher at ~15mm+ (vs. 14.5mm) and same 20mm lug width. Add to that the beefier case/lugs (& CGs) and I had a slight feeling of a top-heavy look. Nothing too dramatic, mind you, yet noticeable. I then gave the 126600 a try. Again, similar (15.25mm) height, but with the added 3mm in diameter as well as the 22mm lug width. Furthermore, the lugs appear to have been modeled a little closer to the classic shape, just a little less "blocky", at least to my eyes. Thus, instead of the SD50 appearing all that much larger, I honestly had the impression that it looked better proportioned and nicely "balanced", for lack of a better term.
The truly next-gen Sea Dweller
But what about that cyclops? And what other factors were there in my decision-making? So let's first cover what may be the most significant difference. Despite the five-year hiatus, the 116600 was fitted with the very same 3135 movement first introduced with the 16600 (& 16800) in the eighties. The 3135 is a workhorse, tried and true with many years of field experience. In the last 10 years, it's also seen modest improvements, such as the inclusion of Rolex's parachrom hairspring. The 126600 on the other hand, is fitted with Rolex's relatively new 3235 (based on the 3255 of the 2015 Day-Date 40). Highlights of the 3235 are the new Chronergy escapement and improved mainspring giving the 3235 a massive jump from 48 to 70 hours power reserve. Additionally, the 3235 has a more efficient (automatic) winding system to handle the additional PR. I say highlights because the 3255 is almost an entire redesign. Last but not least, Rolex increased the accuracy-tolerances of their "Superlative-Chronometer" certification to +/-2s daily!
taken from Rolex's official website
Ah yes, lest we forget, the cyclops. I've never even pondered why Rolex applied the cyclops to their very first Submariner Date, the 1680 back in '67. I was simply used to date complications without a magnification lens and so I was more comfortable with the Sea Dweller's standard date implementation. Even when I could barely read the darn date thanks to my aging eyes... lol. Yep, it took the 126600 and several reviews from professional bloggers to understand the reason behind Rolex's decision back in the 60s, not to apply the lens to the SD. It was simply not feasible to guarantee the cyclops would "survive" the depths the Sea Dweller was rated for. Whether it's based on the adhesive or other aspect in the design is beyond me, but apparently, Rolex has now solved the issue. Thus the reason the 126600 and presumably, all future generations of the SD will come with a cyclops. Aesthetic differences aside, the great news is now I can easily read the date, for a change...!
The (red) cherry on top
Vintage tributes and/or the smallest of details harking back to the first releases of many iconic diver and pilot watches is all the rage now a days. Yet Rolex hasn't looked back all that much, instead, concentrated in bringing their divers up to more contemporary standards (like the beefier cases, ceramic bezels, etc). But what's this... ? A red line of text on the dial of the 126600? Does this not remind us of the past... ? Why yes, it certainly does! Most SD fans will speak of Great Whites, Triple Sixes and last but not least, the venerable Double Red (DRSD). The DRSD may be the most famous of all SDs. Yet the 126600 has only one red line... . Ah, but what is less known is the very first batch of SDs (for professional use only) came with one of the text lines in red: "SEA-DWELLER". This initial SD was a four-liner, while the DRSD actually has five lines of text, the 2nd (red) line being "Submariner 2000*".
*The Single-Red SD also had "Submariner" in the text, but as part of the 2nd line; "Submariner 500m-1650ft".
The one to beat
So it all adds up very quickly - a functional cyclops at depth, the substantial movement upgrade and to my eyes, aesthetic proportions. Add to that the nod to the very first SD with the "single red" and the Sea Dweller's sixth generation is now the one to beat.
Finally, the big picture...
Cerachrom covered in Platinum fairy dust... or something like that...
L.E.C. aka Laser-Etched Crown (Coronet)...
aaaah, the famous Oysterlock...
...with its impressive Glidelock... 20mm in 2mm increments...
...and let's not forget the fliplock, for an instant ~26mm!
Modern meets retro...
A Short chronology of the Sea Dweller
The following paragraphs are taken from my writeup on the 16600
1665 - The first "official" Sea Dweller, released in 1971, came into existence after saturation-diving incidents where the french professional diving company COMEX and the U.S. Navy's Sea-Lab team discovered the adverse effects of helium during the decompression phases following a saturation dive. Thus the birth of the Sea Dweller and its gas escape valve* (aka HEV since Helium is the gas used in saturation diving). The 1665 was rated to 2000ft/610m which was roughly three times the rating of  production Submariners (660ft/200m) of the same period. The 1665 model includes the famous "DRSD" or double-red which had the lines Sea-Dweller and Submariner 2000 in red. Rolex eventually stopped using red print and the all-white lettered SDs received the nickname Great white. As a side note, prototype Sea-Dwellers (aka "single red" / SRSD) were produced around 1967, rated to 1650ft/500m and The COMEX-only 5514 version of the 5513 Submariner were fitted with HEVs.
*In order to provide full disclosure, it has been noted that Rolex partnered with DOXA to produce the one-way, escape valve solution and DOXA was first-to-market with their SUB300T (~1969).
The 1665 was superseded in ~1978 by the 16660 (aka triple-six) and some years after by the 16600. The model# change was to signify the move from the 3035 to the 3135 movement. Both had the newer gloss dials with white-gold marker-surrounds (apart from what I assume to be the remainder of 1665's matte dials used with the first batches of 16660s). The case of the 16600 was slightly altered, perhaps to support the new movement. Any other potential differences are unclear to me. The new generation of the Sea Dweller brought about even greater depth-ratings thanks to changes in the case, the replacement of the 1665's plexi with a thick sapphire crystal as well as a notably larger escape valve. These innovations provided the Sea Dweller with an impressive 4000ft/1220m depth rating! The next-gen Submariners, in comparison, managed an increase to 1000ft/300m with the migration to sapphire, improved Triplock crown, etc. Aside from the amazing depth certification, the Sea Dweller also benefited from solid end-links (SEL) and a bracelet with solid center links. Compared to the Submariner's tuna-can hollow links, the SEL & robust bracelet were a considerable improvement. To many a Sea-Dweller fan's dismay, the Sea Dweller was replaced by the Deepsea (DSSD). While the DSSD is an impressive feat of technology as well as an important tribute to Rolex history, it is quite a different animal. As such, many SD fans would have loved to see it released as an independent model and not as the SD's successor... .
A good a place as any...
...to thank the very nice Gent at Bucherer who has helped me more than once in obtaining unobtanium. I'm no VIP by any measure and it's not my purchasing power, rather my passion that has introduced me to some good people in the field!
p.s. my humble Rolex / Tudor family ...just waiting on a Pepsi...