The Longines Hydroconquest is Now a True GMT

A diver and dual time zone.

Longines’ contemporary diver that’s been in the catalogue for over 16 years, the Hydroconquest now gets an upgrade with a new complication. The Hydroconquest GMT is the first model in the line-up with a dual time zone. In contrast to the bolder-looking time-only counterparts, the new GMT is accompanied by a pared-back, legible dial complemented with a unidirectional ceramic bezel and the brand’s latest automatic calibre.

Initial thoughts

The Hydroconquest tends to receive less attention compared to dive watches from other brands in this price range. In my view, this can be ascribed to its dial design that was bold with oversized numerals positioned at six, nine, and 12, yet not particularly distinctive. Longines probably realised this and smartly developed a new timepiece with a practical complication while tweaking the dial layout and getting rid of these oversized numerals.

The shift from oversized numerals to more conventional indices is particularly notable on the green and brown dials where the colours underscore the carefully thought-out design. Purists might argue for eliminating the date window to further streamline the dial, though that would remove one of the key elements of a traditional GMT watch. 

The Hydroconquest GMT is priced at US$2,675 on a NATO strap, with a rubber strap or steel bracelet available for an extra US$100. This is good value, particularly since the watch includes a bona fide GMT function with an independent local-time hour hand, all for less than US$4,000. Although the finer points of the movement doesn’t surpass that found in the Tudor Black Bay GMT, the Hydroconquest GMT has the advantage of a range of dial colours and bracelet options.

A diver-GMT

The GMT is the latest addition to the Hydroconquest, a collection of modern dive watches introduced in 2007 notable for a bold dial with large numerals (Longines also offers several vintage-inspired dive watches that look decidedly more retro).

The dial is available in four colours: green, blue, black, and brown. The blue and black dials are more contemporary with their silvered hands and indices, while the green and brown dials have gilded elements for a more vintage feel.

All dials feature sun-ray brushing and are complemented by a unidirectional ceramic-insert bezel in the same colour. Featuring a look comprising a combination of baton and round hour markers along with a triangle at 12, the Hydroconquest GMT dial features a two-tone 24-hour ring on its periphery and a date at three o’clock.

Because the Hydroconquest is a dive watch first, the bezel insert is engraved with an elapsed-time scale for scuba diving, rather than the conventional second time zone scale found on most GMT watches. The second time zone is instead found on the 24-hour ring that is read in tandem with the home time hand, allowing the wearer to distinguish between day and night.

Apart from these design modifications, the timepiece remains true to the Hydroconquest template. The stainless steel case has a screw-down crown and water resistance of 300 m. It measures 41 mm in diameter and 12.90 mm high. Because of the GMT function, it is a hair thicker compared to the 41 mm time-only models, standing just 1 mm taller.

The Hydroconquest GMT is equipped with the new L844.5, an ETA-based automatic movement developed exclusively for Longines and essentially identical to the L844.4 found in the Spirit Zulu Time. As with modern Longines calibres, the L844.5 is COSC-certified and offers a healthy power reserve of 72 hours. 

The L844 series movement was designed from the ground up as a GMT, rather having the GMT function as an add on, explaining the independently-adjustable local time hour hand that makes it a true GMT calibre.

Key facts and price

Longines Hydroconquest GMT
Ref. L3.790.4.06.2/6 (green)
Ref. L3.790.4.66.2/6 (brown)
Ref. L3.790.4.56.6/9 (black)
Ref. L3.790.4.96.6/9 (blue)

Diameter: 41 mm
Height: 12.90 mm
Material: Steel
Crystal: Sapphire
Water resistance: 300 m

Movement: L844.5
Functions: Hours, minutes, seconds, date and second time zone
Winding: Automatic
Frequency: 25,200 beats per hour (3.5 Hz)
Power reserve: 72 hours

Strap: Steel bracelet with folding clasp; with the fabric strap option only for the green and brown models and the rubber strap option only for the black and blue models.

Limited edition: No
Availability: At Longines boutiques and retailers
Price: US$2,675 (fabric strap models); US$2,775 (matching bracelet and rubber strap models)

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