Longines HydroConquest Hydroconquest Chronograph

Reference L3.644.4.56.6

About this watch

The Longines Hydroconquest Chronograph L3.644.4.56.6 is a stunning combination of style, functionality, and reliability. With its robust build, it promises durability while ensuring that you look good whether you’re at the beach or in a boardroom meeting. The case is made from high-quality stainless steel, creating a balanced presence on the wrist. The black dial features mixed indexes providing a sporty vibe while ensuring easy readability. The chronograph sub-dials are well-placed, making it simple to track time in various ways. At the core of this watch is the renowned ETA caliber 7750 automatic movement, celebrated for its reliability and precision. The sapphire glass ensures that the watch remains clear and legible no matter the conditions you put it through. With a water resistance rating of 300 meters, the Hydroconquest Chronograph is more than just a pretty face; it's a true diving companion.

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Key Features

41mm diameter stainless steel case
Sapphire glass for scratch resistance
Renowned ETA caliber 7750 automatic movement
Chronograph feature with easy-to-read sub-dials
Water resistance of up to 300 meters
Robust and durable design
Proprietary hands for a unique touch

Specifications

Brand

Longines

Family

HydroConquest

Model

Hydroconquest Chronograph

Reference

L3.644.4.56.6

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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View listing on r/WatchExchange

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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