Longines Hydroconquest Automatic 42 Stainless Steel / Black / Bracelet L3.788.4.56.6

Longines Hydroconquest Automatic 42 Stainless Steel / Black / Bracelet Ref. L3.788.4.56.6

The Longines Hydroconquest Automatic 42 Stainless Steel / Black / Bracelet L3.788.4.56.6 has a 42 mm ceramic case, measures 11.7 mm thick, and is water resistant to 300 metres.

The Longines HydroConquest L3.788.4.56.6 debuted in 2026 as part of the HydroConquest collection, Longines’ line of contemporary dive watches designed for professional water resistance and everyday durability. The model follows the design direction introduced with the HydroConquest GMT in 2024, which revised the collection’s dial layout and finishing. The round stainless steel case measures 42 mm in diameter and is equipped with a screw-in crown and a unidirectional rotating bezel fitted with a ceramic insert. Water resistance is rated to 30 bar. The watch is fitted with a scratch-resistant sapphire crystal with several layers of anti-reflective coating applied to both sides. The dial is finished in black with a polished lacquered surface. Applied indexes serve as hour markers, reflecting the updated HydroConquest design that no longer features Arabic numerals on the dial. Silvered polished hands indicate the time, while a date display completes the functional layout. Power is provided by the Longines calibre L888, a self-winding mechanical movement beating at 25,200 vibrations per hour. The movement is equipped with a monocrystalline silicon balance spring and offers a power reserve of approximately 72 hours. It drives the central hours, minutes, and seconds together with the date indication. The L3.788.4.56.6 is fitted with a stainless steel bracelet secured by a double security folding clasp with a micro-adjustment system.

Diameter
42 mm
Thickness
11.7 mm
Water resistance
300 m
Case
Ceramic
Released
2026

Specifications

Case and dimensions

Case diameter
42 mm
Thickness
11.7 mm
Lug width
21 mm
Case shape
Round
Case material
Ceramic and Stainless Steel
Bezel
Rotating, 0-60 (Dive)
Crystal
Sapphire
Case back
Closed
Water resistance
300 m

Dial

Dial colour
Black
Finish
Gloss
Indexes
Stick / Dot
Hands
Proprietary

Movement

Movement maker
Longines
Movement type
Automatic
Display
Analog
Power reserve
64 h
Frequency
25200 vph
Jewels
21
Movement diameter
25.6 mm
Complications
Chronometer, Date, Hours, Minutes and Seconds

Production

Release year
2026

Marketplace

No listings for this model yet.

Other HydroConquest references

12
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