Longines HydroConquest Hydroconquest Automatic 39 Black

Reference L3.641.4.56.6

About this watch

The Longines Hydroconquest Automatic 39 Black is a testament to the perfect fusion of functionality and sophistication, designed for both adventure and elegance. With its stunning black dial and striking stick and dot indexes, it offers a beautiful contrast that catches the light beautifully. The 39mm stainless steel case strikes a perfect balance between robust and refined, making it comfortable for everyday wear while still being tough enough for underwater adventures. At the core of this timepiece lies the Longines caliber L633.5, an automatic movement based on the renowned ETA 2824-2. This movement is celebrated for its reliability and accuracy, ensuring precise timekeeping with a frequency of 28,800 vibrations per hour. The Hydroconquest boasts a power reserve of approximately 38 hours, making it ideal for everyday wear. With a water resistance rating of 300 meters, this watch is designed to handle the pressure of aquatic activities. Its rotating bezel with a 0-60 scale allows you to track elapsed time underwater, ensuring your safety while looking incredibly stylish.

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Key Features

39mm stainless steel case
Longines caliber L633.5 automatic movement
Sapphire crystal glass for scratch resistance
300m water resistance
Rotating 0-60 bezel for dive tracking
Stainless steel bracelet with adjustable clasp

Specifications

Brand

Longines

Family

HydroConquest

Model

Hydroconquest Automatic 39 Black

Reference

L3.641.4.56.6

Movement

l633-5

Movement Features

Hours, Minutes, Seconds
Date

Case

Stainless Steel 39mm

Dial Color

Black

Crystal

Sapphire

Water Resistance

300

Current Listings

Longines HydroConquest L3.788.4.06 — 42mm Ceramic Bezel — Full Kit — 11 Days Old — $1999 Shipped 🔥

Longines - L3.788.4.06 · $1,999

This Longines HydroConquest features a modern configuration with a ceramic bezel and is practically new at just 11 days old.

Condition: Excellent overall, only very light hairlines present
Age: 11 days
Dimensions: 42mm diameter

Posted at

Apr 25, 2026, 8:50 PM

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Longines Conquest 39 mm $600 and Longines HydroConquest 39 mm $700

Longines - L3.776.4, L3.741.4 · $600

Two Longines watches for sale, the Conquest L3.776.4 and the HydroConquest L3.741.4.

Condition: Very good
Case size: 39 mm
Year purchased: 2025
Clasp wear: minor wear on clasp from being stored at work desk

Posted at

Apr 25, 2026, 1:54 PM

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Longines HydroConquest 41 – $975

Longines - HydroConquest 41 · $975

This Longines HydroConquest 41 features a 41mm case, minimal wear, and comes with its box, papers, hangtag, and warranty card.

Condition: Very Good Pre-owned Condition
Case Size: 41mm diameter
Bracelet Condition: hairlines throughout polished surfaces, some desk wear

Posted at

Apr 25, 2026, 10:32 AM

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Brand New Longines Hydroconquest Exclusive- 42mm- L3.788.4.98.6

Longines - L3.788.4.98.6 · $2,200

The Longines Hydroconquest Exclusive features a 42mm case with a beautiful frosted blue dial and comes in brand new condition.

Condition: Brand new, unworn
Case size: 42mm

Posted at

Apr 24, 2026, 6:24 PM

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New Longines HydroConquest 42mm

Longines - HydroConquest 42mm · $2,050

A new Longines HydroConquest in the 42mm size, with a mesh band and box and papers included.

Condition: New
Case Size: 42mm
Band Type: mesh

Posted at

Apr 23, 2026, 8:54 AM

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Longines Hydroconquest Chronograph 41 Ref. L3.783.4 – Travel Box & Manual | $1,850

Longines - L3.783.4 · $1,850

The Longines Hydroconquest Chronograph is a high-performance Swiss diver's watch that features a 41mm case, blue ceramic bezel, and screw-down crown. It houses the calibre L688.2, a column-wheel chronograph movement with a 54-hour power reserve.

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

Posted at

Apr 22, 2026, 3:35 PM

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