As two of the most well-known models among Rolex’s sport watch lineup, the Submariner and the GMT-Master have accompanied each other in the Rolex catalogue since the mid-1950s. Historically, they have always been very different watches; however the most recent stainless steel incarnations of Rolex’s Submariner and GMT-Master – the reference 116610 and the reference 116710, respectively – are remarkably similar timepieces.

Design: Submariner ref. 116610 vs. GMT-Master II ref. 116710

Both the reference 116610 Submariner and the reference 116710 GMT-Master II are 40 mm in diameter and use Rolex’s redesigned “super case” that has thicker lugs and crown guards for a more bold and chunky overall appearance. This redesigned case first made an appearance in 2007 with the introduction of the reference 116710 GMT-Master II, and then was carried over on to the Submariner line of watches a year later.

Additionally, both watches are fitted with Rolex’s Triplock winding crown for improved water resistance. Rolex has been using the Triplock crown on the Submariner for a number of years; however the reference 116710 marks the first time that it has been an appearance on the GMT-Master line of watches. Despite the addition of the Triplock winding crown, the reference 116710 GMT-Master II has retained the same 100-meter depth rating of the previous model.

Although both watches are fitted with black bezel inserts made from Rolex’s proprietary Cerachrom ceramic compound, the inserts themselves are marked differently to be better suited to the two watches’ respective intended tasks. The bezel insert on the Submariner features a 60-minute scale with a luminous dot implanted on the 0-minute marker, so that the bezel of the watch can be used as a dive timer. The bezel insert on the GMT-Master II is marked with a 24-hour scale, for use in conjunction with the GMT hand for referencing an additional time zone.

Movements: Submariner ref. 116610 vs. GMT-Master II ref. 116710

The key difference between the reference 116610 Submariner and the reference 116710 GMT-Master II is the movement that is fitted inside the two watches. The GMT-Master line has always had a 4th GMT hand in order to display a secondary time zone, and as a result, it requires a different movement than traditional 3-hand, self-winding watches.

The reference 116610 Submariner is fitted with Rolex’s venerable Caliber 3135 movement that has been around, largely unchanged, since 1988. The Caliber 3135 is a conventional 3-hand, automatic movement with a date complication that has been used throughout Rolex‘s various lines of men’s watches for over a quarter of a century.

The reference 116710 GMT-Master II receives Rolex’s in-house Caliber 3186 movement, which has both a date complication, and an independently adjustable hour hand. Although the GMT-Master line has always had a 4th GMT hand, Rolex’s GMT-Master II watches replica allow the traditional hour hand to be set independent of the GMT hand, enabling owners to reference three time zones simultaneously when used in conjunction with the GMT’s rotating 24-hour bezel.

Subtle Differences: Submariner vs GMT-Master II

Although the reference 116610 Submariner and the reference 116710 GMT-Master II are visually very similar watches, there are a few key variations that help distinguish them as two separate lines of Rolex sport watches. The different movements, bezels, and number of hands, are the most noteworthy areas in which the two watches are distinct; however there are also minor differences that help set the two watches apart.

Although the two watches are remarkably similar and share the same Triplock winding crown, the reference 116610 Submariner has a depth rating of 300 meters, while the reference 116710 GMT-Master II is only rated to a depth of 100 meters. One of the factors that may be partly responsible for the Submariner’s superior depth rating is its thicker, more convex case-back, which is better equipped to withstand the extreme pressures present deep below the surface of the ocean.

While both watches are fitted with the latest generation of Rolex’s Oyster bracelet, both the style of clasps and the polish on the links is done differently on the reference 116610 and the reference 116710. Although both clasps feature Rolex’s Oysterlock safety closure system, only the bracelet on the Submariner is fitted with Rolex’s Glidelock extension system for use with a wetsuit. Additionally, the center links of the bracelet on the GMT-Master II receive a high-gloss polish, while the Submariner’s bracelet is entirely brushed with a satin finish.

Lastly, both the 24-hour hand and GMT-Master II name on the dial of the reference 116710 are finished in green paint to match Rolex’s company colors. The Submariner on the other hand, retains its iconic, entirely black and white color profile, which helps to visually distinguish the two watches and allow each to have its own image and identity.

The Submariner and the GMT-Master have always been parallel watches that were offered along side one other in the Rolex catalogue. However the most recent iterations of these legendary sport watches have brought the two lines closer together than ever before. Although the two watches are actually very different when it comes to their internal movements and intended purposes, their overall aesthetic is so similar, that selecting between the two is really a matter of which watch is better suited to the needs and lifestyle of its individual owner.