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 Blue 39mm - $1150

Longines - Hydroconquest · $1,150

A blue dial Longines Hydroconquest 39mm watch with a full kit, in excellent condition and keeping good time.

Condition: Great condition
Year purchased: 2025
Warranty duration: 5 years

Posted at

Mar 1, 2026, 8:14 PM

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Longines Hydroconquest 41mm Two Tone

Longines - Hydroconquest 41mm Two Tone · $999

A Longines Hydroconquest 41mm Two Tone watch with a black dial and two tone finish. It is in very good condition with some minor wear.

Condition: Very Good Pre Owned Condition
Diameter: 41mm

Posted at

Feb 27, 2026, 3:34 PM

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Longines HydroConquest GMT 41mm L3.790.4

Longines - L3.790.4 · $1,799

This Longines HydroConquest GMT is a 41mm watch featuring a 6.5 inch bracelet and an aftermarket rubber strap with deployant.

Bracelet Length: 6.5 inches
Case Size: 41mm

Posted at

Feb 19, 2026, 5:35 PM

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Longines HydroConquest 43mm Automatic – Black Dial – Full Kit – $1,095

Longines - L3.782.4 · $1,095

This Longines HydroConquest automatic watch features a black dial and 43mm case size, which provides a strong wrist presence.

Condition: very good
Case size: 43mm diameter
Case wear: normal wear consistent with careful use

Posted at

Feb 18, 2026, 4:40 PM

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Longines Hydroconquest 41m Green full kit with OEM bracelet and rubber strap

Longines - Hydroconquest 41m · $975

A green ceramic automatic watch from Longines, part of the Hydroconquest series, featuring a Swiss movement with 72-hour power reserve.

Condition: Used with signs of wear
Case diameter: 41 mm
Water resistance: 300m / 30 bar
Movement: Longines Calibre L888 series with 72hr power reserve

Posted at

Feb 16, 2026, 4:12 PM

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Longines HydroConquest, L3.781.4.06.9, Steel Diver, Olive, Excellent Condition.

Longines - L3.781.4.06.9 · $1,095

This Longines HydroConquest is a steel diver's watch with an olive green matte dial and a unidirectional rotating ceramic bezel. The stainless steel case measures 41mm in diameter and has a water resistance of up to 300 meters.

Condition: Excellent Condition
Case Diameter: 41mm
Thickness: 11.9mm
Bezel Type: Unidirectional rotating Green Ceramic

Posted at

Feb 5, 2025, 2:47 AM

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