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

[WTS] Longines Hydroconquest Quartz Two Tone L3.740.3.56.7 - $550

Longines Hydroconquest Quartz Two Tone L3.740.3.56.7 - $550

A Longines Hydroconquest quartz two-tone diver watch, featuring a black dial and 41mm case size.

  • Condition: Pre-owned with light scratches
  • Case size: 41mm
  • Material: two tone
Posted at
May 17, 2026, 9:13 AM
Active
[WTS] Longines Hydroconquest Quartz Two Tone L3.740.3.56.7 - $550

Longines Hydroconquest Quartz Two Tone L3.740.3.56.7 - $550

This Longines Hydroconquest is a fun and capable diver that comes in the 41mm version, featuring a black dial and quartz movement.

  • Condition: pre-owned with light scratches
  • Case Size: 41mm
  • Movement Type: quartz
Posted at
May 16, 2026, 7:05 PM
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[WTS] Longines Hydroconquest 39mm black bezel/dial

Longines Hydroconquest 39mm black bezel/dial

This Longines Hydroconquest 39mm features a black bezel and dial, is in excellent condition, and comes with its full kit including boxes, hangtags, warranty card, and owner's manual.

  • Condition: Like-new
  • Case size: 39mm diameter
  • Box status: full-kit
  • Warranty remaining: five years
Posted at
May 16, 2026, 5:17 PM
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[WTS] Longines HydroConquest Two Tone Green Dial $1499

Longines HydroConquest Two Tone Green Dial $1499

Longines - HydroConquest · $1,499
Longines HydroConquest Two Tone Green Dial for sale

Posted at
May 16, 2026, 11:33 AM
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[WTS] Longines HydroConquest 42mm | 2026 Gen | Green Ceramic | Green Lacquered Dial | Ref. L3.788.4.06.6 | Never Sized, Never Worn | Full Kit | Warranty Card 5/8/26

Longines HydroConquest 42mm | 2026 Gen | Green Ceramic | Green Lacquered Dial | Ref. L3.788.4.06.6 | Never Sized, Never Worn | Full Kit | Warranty Card 5/8/26

Longines - L3.788.4.06.6 · $1,999
This is the first real redesign the HydroConquest has seen in nearly a decade with thinner case and upgraded ceramic bezel with audible click.

  • Condition: Never sized, never worn
  • Movement: Calibre L888.5, automatic, silicon balance spring, 72hr power reserve
  • Water resistance: 300m / 30 bar
  • Box papers: Full double-box set with instruction manual and tags present
Posted at
May 16, 2026, 10:58 AM
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[WTS] Longines Hydroconquest 41mm Black dial

Longines Hydroconquest 41mm Black dial

Longines - L3.781.4.56 · $1,100
A Longines Hydroconquest 41mm with a black dial is being sold. The watch features an original box and bracelet, as well as two additional straps.

  • Condition: Very good condition, a few scuffs on the sapphire but no scratches
  • Case size: 41mm
  • Bracelets: 2
  • Straps: 2
Posted at
May 15, 2026, 2:06 PM
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[WTS] Longines Hydroconquest 39mm L3.779.4.96.6

Longines Hydroconquest 39mm L3.779.4.96.6

Longines - L3.779.4.96.6 · $2,100
A Longines Hydroconquest 39mm with a frosted blue dial, this watch features a unique and stylish design.

  • Condition: Like new
  • Size: 39mm diameter
Posted at
May 14, 2026, 10:43 PM
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[WTS] Longines Hydroconquest 39mm

Longines Hydroconquest 39mm

A Longines Hydroconquest diver's watch in excellent condition, featuring a 2026 movement and virtually no signs of wear.

  • Condition: 9.6/10 - extremely clean example
  • Movement: 2026
  • Case condition: virtually no signs of wear
  • Box included: true
Posted at
May 14, 2026, 10:36 PM
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[WTS] Longines Hydroconquest 39mm Limited Edition Commonwealth Games Mint

Longines Hydroconquest 39mm Limited Edition Commonwealth Games Mint

Longines - L3.779.4.09.9 · $2,950
A limited edition Longines Hydroconquest, purchased just a week ago and still under warranty.

  • Condition: Mint
  • Case Size: 39mm
  • Limited Edition Quantity: 2026 pieces
  • Warranty Length: five years
Posted at
May 12, 2026, 4:37 PM
Active