Longines HydroConquest Hydroconquest Chronograph

Reference L3.644.4.56.2

About this watch

The Longines Hydroconquest Chronograph (Model L3.644.4.56.2) is a stunning piece that combines sophistication with robust functionality. Founded in 1832, Longines has a rich heritage in watchmaking that spans nearly two centuries. The Hydroconquest line is designed for those who appreciate both style and performance. This timepiece is powered by the revered ETA 7750 movement, an automatic movement providing reliable and accurate timekeeping experience with a frequency of 28,800 vibrations per hour and a power reserve of 42 hours. The watch features a gem-set bezel, stainless steel case with a water resistance of up to 300 meters, and a black dial with mixed indexes for high visibility. The proprietary hands are designed for readability, ensuring quick time-telling in low-light conditions. With its impressive water resistance and robust chronograph functionality, this watch is perfect for divers, snorkelers, and anyone who appreciates luxury and performance.

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Key Features

ETA 7750 automatic movement
Water resistance up to 300 meters
Gem-set bezel
Stainless steel case
Black dial with mixed indexes
Proprietary hands for readability
Robust chronograph functionality

Specifications

Brand

Longines

Family

HydroConquest

Model

Hydroconquest Chronograph

Reference

L3.644.4.56.2

Movement

7750

Movement Features

Hours, Minutes, Small Seconds
Date, Day
Chronograph

Case

Stainless Steel 41mm

Dial Color

Black

Crystal

Sapphire

Water Resistance

300

Current Listings

Longines HydroConquest GMT 41mm Black, Full Kit, June 2025

Longines - HydroConquest GMT · $1,980

Up for sale is my mint condition Longines HydroConquest GMT, a full kit with box, papers, tags, and over 4 years left on the factory warranty.

Condition: Mint condition
Case dimensions: 41mm diameter, 49mm lug to lug, 12.9mm thickness
Movement: L844.5 with 72hrs power reserve
Water resistance: 300m

Posted at

Apr 19, 2026, 10:47 PM

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Longines Hydroconquest 39mm Black MINT

Longines - Hydroconquest 39mm Black · $2,200

A mint condition Longines Hydroconquest 39mm in black with a super comfortable bracelet and excellent bezel action.

Condition: MINT
Bracelet type: Super comfortable bracelet
Clasp type: Excellent on the fly clasp
Bezel action: Great bezel action

Posted at

Apr 19, 2026, 9:12 AM

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Longines HydroConquest 39mm Green Ceramic Bezel 2026 NEW L3.779.4.06.6 – $2800 + shipping

Longines - L3.779.4.06.6 · $2,800

This Longines HydroConquest features a stunning green ceramic bezel and matching dial, with a 39mm size that wears well on the wrist.

Condition: Brand new
Case Size: 39mm diameter
Bezel Material: green ceramic

Posted at

Apr 17, 2026, 6:00 AM

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2026 Longines Hydroconquest 39mm - Grey Bezel / Black Dial

Longines - L3-779-4-70-6 · $2,100

This 2026 Longines Hydroconquest is a 39mm grey bezel/black dial watch, purchased directly from Longines and regularly worn. It's free of major scratches or dents but has minor wear on the back of one lug.

Condition: Excellent to LNIB (like new in box)
Bracelet length: up to an 8in wrist
Bent link pin: one link pin is bent and unusable
Included accessories: all original packaging, accessories, and paperwork

Posted at

Apr 16, 2026, 3:09 PM

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Longines HydroConquest Sunray Blue- L3.790.4.96.6

Longines - L3.790.4.96.6 · $2,900

A brand new Longines HydroConquest with sunray blue dial, featuring a new box and papers.

Condition: Brand new
Box And Papers: brand new

Posted at

Apr 16, 2026, 12:11 PM

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[WTS] Longines HydroConquest GMT - Unworn, Full Set, Black Dial 41mm. The watch is in completely unworn condition and comes as a full set including box, papers, and all original accessories. Price:1700. UK-based. Happy to ship or meet depending on location. Dm if interested

Longines HydroConquest GMT - Unworn, Full Set, Black Dial 41mm. The watch is in completely unworn condition and comes as a full set including box, papers, and all original accessories. Price:1700. UK-based. Happy to ship or meet depending on location. Dm if interested

Longines - HydroConquest GMT · $1,700

The Longines HydroConquest GMT is a 41mm timepiece that comes as a full set including box, papers, and all original accessories. It is in completely unworn condition.

Condition: Unworn
Case Size: 41mm
Set: Full set including box, papers, and all original accessories

Posted at

Apr 16, 2026, 11:26 AM

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Longines Hydroconquest GMT 41mm Black (Nov 2024)- $2950 AUD (Sydney, Australia)

Longines - L3.826.4.53.2 · $2,950

a black Longines Hydroconquest GMT watch with a 41mm case size.

Material: Stainless Steel
Diameter: 41mm
Depth rating: 300m

Posted at

Apr 16, 2026, 9:54 AM

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Longines HydroConquest 41mm

Longines - L3.781.4.96.6 · $1,100

A Longines HydroConquest 41mm watch with a blue sunburst dial, featuring a clean crystal and flawless dial.

Condition: Excellent pre-owned condition
Diameter: 41mm

Posted at

Apr 15, 2026, 3:43 PM

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Longines Hydroconquest Chronograph 41 Ref. L3.783.4 – Travel Box & Manual | $1,900

Longines - L3.783.4 · $1,900

This Longines Hydroconquest Chronograph is a high-performance Swiss diver's watch featuring a blue ceramic bezel and screw-down crown, powered by the calibre L688.2 column-wheel chronograph movement with a 54-hour power reserve.

Condition: Very good with minor usage marks
Case Size: 41mm x 51mm stainless steel case, 15.6mm thickness, 21mm lug width
Movement: Longines L688.2 automatic column wheel chronograph with 27 jewels, 28,800 bph, and a 54-hour power reserve
Water Resistance: 300m (30 ATM)

Posted at

Apr 15, 2026, 11:30 AM

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