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.

Buy Now on Jomashop

This is an affiliate link

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 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

View listing on r/WatchExchange

Longines HydroConquest 39mm Automatic Black Ceramic Bezel + Bracelet + WOE NATO - $750

Longines - HydroConquest 39mm · $750

This Longines HydroConquest is an excellent daily-wear diver with great proportions and comfortable sizing, featuring a black dial and ceramic bezel. The watch is running well and keeping great time.

Condition: Excellent daily-wear, shows wear from use on the bracelet
Case Size: 39mm diameter
Bracelet Type: black ceramic bezel + bracelet + WOE NATO

Posted at

May 12, 2026, 4:18 PM

Active

View listing on r/WatchExchange

Longines Hydroconquest Quartz Two Tone L3.740.3.56.7 - $600 🚢

Longines - L3.740.3.56.7 · $600

A quartz-powered diver's watch from Longines, featuring a black dial and two-tone yellow gold PVD finish on the 41mm case.

Condition: Good (light scratches)
Case size: 41mm
Material: two tone yellow gold PVD
Movement: quartz

Posted at

May 10, 2026, 5:48 PM

Active

View listing on r/WatchExchange

Longines Hydroconquest 43mm (updated pictures)

Longines - L3.782.4.56.6 · $1,260

This Longines Hydroconquest 43mm features a black dial on a stainless steel bracelet and has been worn only 4-6 times since its purchase. It comes with a full set, including the box, tags, warranty cards, and is still under Jomashop's 2-year warranty.

Condition: Fantastic, worn 4-6 times
Case size: 43mm
Lug to lug: 53mm
Thickness: 11.90mm

Posted at

May 9, 2026, 4:10 PM

Active

View listing on r/WatchExchange

(brand new) Longines HydroConquest 39mm - $1800 shipped

Longines - HydroConquest · $1,800

This brand new Longines HydroConquest features a black dial, stainless steel case and bracelet, sapphire crystal with anti-reflective coating, and is powered by the L888.4 automatic movement.

Condition: Unworn
Case material: stainless steel
Bracelet material: stainless steel
Water resistance: 300m

Posted at

May 9, 2026, 1:11 PM

Active

View listing on r/WatchExchange

2026 Longines HydroConquest 39mm - Black Ceramic - Newest Release - Full Set

Longines - L3.779.4.56.6 · $1,900

The newly redesigned Longines HydroConquest in the highly sought-after 39mm size, featuring a refined dial and upgraded bracelet.

Condition: Excellent Used Condition
Size: 39mm diameter
Thickness: ~11.9mm
Lug-to-lug length: 47mm

Posted at

May 7, 2026, 8:43 PM

Active

View listing on r/WatchExchange

Longines Hydroconquest 43mm L3.782.4.56.6-3 weeks owned.

Longines - L3.782.4.56.6 · $1,350

A Longines Hydroconquest 43mm watch on a black dial with a stainless steel bracelet, now on an Ali Rubber strap.

Condition: Mint condition, worn approximately 5 times
Case size: 43mm diameter
Lug to lug: 53mm
Thickness: 11.90mm

Posted at

May 7, 2026, 4:43 AM

Active

View listing on r/WatchExchange

Longines Hydroconquest Quartz Two Tone L3.740.3.56.7 - $600 🚢

Longines - L3.740.3.56.7 · $600

This Longines Hydroconquest is a 41mm two-tone diver's watch with a quartz movement.

Condition: Used with light scratches
Size: 41mm diameter

Posted at

May 6, 2026, 9:43 PM

Active

View listing on r/WatchExchange

2025 Longines Hydroconquest 41mm Ref: L37814056

Longines - L37814056 · $1,300

This listing is for a 2025 Longines Hydroconquest 41mm watch, featuring an automatic self-winding caliber L888.5, unidirectional green ceramic bezel, and 300M water resistance.

Condition: Like new with some minor marks on the bracelet and buckle
Case size: 41mm
Bracelet type: Stainless steel
Water resistance: 300m depth rating

Posted at

May 6, 2026, 8:37 PM

Active

View listing on r/WatchExchange