The Omega Seamaster Professional clasp was both sturdy and attractive

In 45 years of diving, I have seen the good, the bad and the ugly of dive watch bracelets and clasps.

For many years, the best I’ve used was the foldover clasp on the Omega Seamaster Professional, first introduced in the early-1990s. Its heavy, machined parts and precise operation made you feel confident in its functioning – above and below the surface – as well as delighted with its aesthetic appeal.

The heavy-duty, precisely machined components of the SMP clasp

And I found the flip-out divesuit extension to work quite well, at least when I dived in waters cold enough to require a wetsuit (I’m a committed warm water diver now).

The runner-up for most of those years was Rolex’s redoubtable Fliplock clasp, used on the Submariner and Sea Dweller models. I bought my first Submariner in 1981, to replace the Omega Seamaster 300 that had been lost a few years before. By this time, Rolex was using solid machined links, of which the ones closest to the clasp were removable by way of a threaded pin. Coupled with the micro-adjust holes in the clasp, the bracelet could be precisely fitted to any wrist and to suit any tastes.

The Fliplock featured a safety clasp that locked the clasp in place once closed, so that it could not pop open accidentally. It also had a flip-out divesuit extension, but it was stamped metal like the clasp. In fairness, while this seemed a bit flimsy in retrospect – especially compared to the beefier Omega extension – it always functioned as it should on dives and I never had any problems with it on dozens of dives.

The ‘ratcheting’ clasp on the Doxa 5000T

But, compared to the Seamaster Pro bracelet and clasp, the Sub bracelet no longer seemed the apotheosis of design I had theretofore considered it to be. I often considered buying another Submariner, but kept deciding against it because of the thin, “jangly” clasp.

In the past few years, another clasp – commonly referred to in dive watch circles as the “ratcheting” clasp – has exceeded even the Seamaster Pro clasp as especially well-suited for underwater use. It employs a push-button deployant very similar in design to the Omega clasp, but incorporates a novel divesuit extension that opens by way of another push-button.

The ‘ratcheting’ clasp on the UTS 1000m

Once fully extended – which adds from 12 to 18mm to the length of the bracelet – the clasp is “ratcheted” to a snug fit around one’s wrist (presumably over a divesuit). While variations of the design apparently have been around awhile, it has been extensively promoted on models for Doxa, UTS and Boschett.

But everything changed when Rolex introduced the Sea Dweller Deepsea in 2008. Among its many features was the new Glidelock clasp. Gone were the stamped metal parts of the Sea Dweller and Submariner clasps. Instead, Rolex had designed an entirely new clasp made from cast and machined parts. The closing mechanism used an articulating claw clasp, which provided a very positive “click” when closed, and opened by lifting the hinged head of the clasp, disengaging the claw. Even better, the clasp incorporated an incremental divesuit extension – dubbed Glidelock by Rolex – which allowed a diver to increase the bracelet length a total of 18mm, in 1.8mm increments. In addition, a much sturdier, machined fold-out divesuit extension was provided, allowing another 26mm of lengthening.

The Glidelock clasp on the Deepsea

The Glidelock mechanism worked by lifting the center part of the clasp, which incorporated ratchets to lock the bracelet lengthening when closed. Once lifted, the bracelet could be slid out to lengthen or in to shorten, allowing for a precise fit. Once adjusted, the center section closed to lock the bracelet at that length. Rolex’s safety clasp, which also was beefed up to a machined piece rather than the old stamping, provided the final assurance that the clasp would remain intact during strenuous use underwater.

The completely re-engineered dive clasp of the Rolex Deepsea and Submariner

Two years later, Rolex updated the venerable Submariner with many of the new features on the Deepsea, including a ceramic bezel and a slightly different version of the Glidelock clasp. Rather than a separate section in the center of the clasp that lifted to free the ratcheting mechanism, the Submariner clasp had the ratchet notches cast into the clasp itself, which was substantially thicker than its predecessor. The locking mechanism was incorporated into the links, which, when released, allowed the bracelet to slide out of or back into the clasp, with a full 20mm of adjustment in 2mm increments – enough to expand the bracelet to fit over a typical 3mm wetsuit.

The Rolex Glidelock clasp on the new Submariner

For years, dive watch enthusiasts who gladly – or grudgingly – paid the prices Rolex demanded for the Submariner had complained that the clasp on the watch did not match up to either the quality of the rest of the bracelet and case, or the selling price. With the advent of the Glidelock, however, Rolex has created a clasp which ranks as among the most utilitarian available to divers, as well as one of the most sturdily crafted. As a bonus, it is beautifully executed and enhances the overall appearance of the watch.

Note: I should point out that Seiko has had a clasp similar in function to the Glidelock on its vaunted Marine Master line. However, the Seiko clasp is made of stamped metal, similar to the old Rolex clasps, and exposes an unsightly pierced link when the extension is employed. While almost equally functional, the execution on the Seiko MM clasp pales in comparison to the Glidelock, especially on a watch that sells for almost $3,000.