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

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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Longines HydroConquest GMT Black. Ref: L3.790.4.56.6 (2025) Complete. $1,950

Longines - L3.790.4.56.6 · $1,950

This Longines HydroConquest GMT Black is a modern dive watch with excellent everyday wearability, offering both tool watch functionality and travel convenience.

Condition: Excellent pre-owned
Case size: 41mm diameter
Water resistance: 300m

Posted at

Apr 14, 2026, 9:45 PM

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(Longines) (2026 Hydroconquest 42) Full 5 Year Warranty, LNIB

Longines - Hydroconquest 42 · $2,200

This newly released Longines Hydroconquest is a large watch with exceptional fit and finish. It comes in its original packaging with a full kit and warranty.

Condition: LNIB (Like New In Box)
Case size: 42mm
Water resistance: not specified

Posted at

Apr 13, 2026, 2:48 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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