The model that succeeded the 1665 was launched in 1978 as the 16660 affectionately known as the "Triple Six". This model was a big leap as it had a depth rating of 4000 feet as opposed to the predecessor with only 2000 feet model 1665. The Sea-Dweller 4000 was the result of the partnership between Rolex and the commercial deep sea diving company COMEX. Rolex developed a helium gas release valve for their needs and was used by the COMEX divers since 1992. The Sea-Dweller 4000 is powered by the same COSC certified Rolex 3135 automatic winding movement that is used on the Submariner. Originally with a 3035 movement (16660) changed late 80's to the 3135 movement which is perfect for what it was intended, solid work horse, accurate mechanical movement with no complications (apart from date). It features a scratch resistant sapphire crystal, unlike the previous 1665 which had a domed plexi and an improved, larger helium escape valve. The watch was designed to feature a glossy dial with metal circled index as in current model 16600. But as we all know Rolex never leaves any dials to waste on the shop floor so the early model 16660 featured the matt dial with painted index markers. I am guessing the painted dials ended around 1987/88ish. This is the model that can currently be found on the market but has been discontinued by Rolex which has replaced it with the DEEPSEA. The DEEPSEA, official depth rating of 3,900 meters (12,800 ft) with a 44mm case diameter (48 mm with crown) and being 18mm thick it is a much heavier piece than the original.
The Sea-Dweller 4000 is assured a place in history as a classic modern Dive watch, a look perfected by Rolex, for decades to come.

Please feel free to make corrections, add omissions and post your Sea-Dweller.
Bill

its has visible signs of use (as it should be) makes it way cool. And your photos captures that extremely well.
The emotion and passion behind your words are evident !
That is indeed in the Hall of Fame !
Rolex and tool watch are synonymous. This is the kind of watch “Modern Sea-Dweller” is the kind of watch you put on and forget you have it on. Before you know it you have had ten years. And yes, shower, sleep, Jog, work, eat and be merry. No worries or concern.
We all know we have to be a little more delicate with some of the vintage specimens but it really relates mostly to water intrusion. It is a good habit to replace the crystal and pressure test the old timers.
Thanks for the comments.
Bill
The sapphire of the modern Rolexes, but the look of a Vintage.
A watch with a vintage look you can wear in all the situations, even during your water activities.
Actually, I thought it was introduced a bit later, around 1981, my friend.
In myopinion, a Double Red is cool in any Vintage Rolex Collection, but we would also need a Triple 6.
Not only a nice one, but a lovely one.
And tjhis nickname " Triple Six "!
Best and thanks for this very cool series of posts, Bill.
When do you write something about the 6542?
Nicolas.
I had to look twice I thought I was looking at my watch on my wrist. But then I saw the Borat outdoor TM SM M&M stamp on the picture. Pure power and beauty.
HAGWE mon ami
A+
Bill
PS my arm hair is more gray as you are still a young man

I think there's kind of a competition between you and Bill to see who thakes the most alluring and gorgeous Rolex picture
¡Un fuerte abrazo compadre!
René
for sure the triple 6 is a mile stone in the history of divers and the pefect transitional model from vintage to modern, keeping some appeal of the vintage on tha painted dial version with some creamy indexes and the features of the modern watches with the saphir!
Matt

Nice one. Modern classic with a touch of class. Coming from your collection we can only assume that whichever example you are going to share with us it's going to be special.
Very nice.
Thanks and HAGWE
Bill
Perfect size for my wrist, reasuringly strong, classic design - among my favorites!
