Longines HydroConquest Hydroconquest Chronograph Tachymeter Black

Reference L3.651.4.56.6

About this watch

The Longines HydroConquest Chronograph Tachymeter Black is a testament to the brand's dedication to creating timepieces that combine functionality, style, and durability. Its striking black dial exudes a sporty yet sophisticated vibe, making it a versatile option for both casual outings and formal events. The watch features a robust movement based on the ETA/Valjoux 7750, boasting a 42-hour power reserve and a frequency of 28,800 vibrations per hour. With its impressive water resistance of 300 meters and sapphire glass protection, this watch is designed to withstand underwater activities while remaining stylish enough for everyday wear. The stainless steel bracelet adds to its luxurious feel, ensuring comfort throughout the day. Whether you're deep-sea diving or just going about your day, you can trust this watch to keep you on schedule. With a diameter of 41.00 mm, it strikes a balance between being prominent on the wrist without feeling bulky.
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Key Features

  • Longines caliber L667 automatic movement
  • 300m water resistance with sapphire glass protection
  • Stainless steel case with rotating dive bezel
  • Black dial with stick and dot indexes
  • Chronograph function with three sub-dials
  • 42-hour power reserve and 28,800 vibrations per hour
  • 41.00 mm diameter and 21.00 mm lug width

Specifications

Brand
Longines
Family
HydroConquest
Model
Hydroconquest Chronograph Tachymeter Black
Reference
L3.651.4.56.6
Movement
l667
Movement Features
  • Hours, Minutes, Small Seconds
  • Date
  • Chronograph
Case
Stainless Steel 41mm
Dial Color
Black
Crystal
Sapphire
Water Resistance
300

Current Listings

[WTS] Reduced! Longines Hydroconquest 41mm ceramic, LNIB literally spotless

Reduced! Longines Hydroconquest 41mm ceramic, LNIB literally spotless

This is a 41mm Longines Hydroconquest with a blue dial and blue ceramic bezel. It has not been worn extensively and comes with the original box and papers.

  • Condition: Like new in box
  • Diameter: 41mm
  • Bezel material: blue ceramic
Posted at
Oct 18, 2025, 8:33 AM
Active
[WTS] Longines HydroConquest – Ceramic Bezel 39mm, 2029 Warranty

Longines HydroConquest – Ceramic Bezel 39mm, 2029 Warranty

A black dial Longines Hydroconquest Ceramic Bezel in 39mm size, bought new in October 2024.

  • Condition: Great condition on the case, crystal, and dial. Minor scratches from daily wear are visible on the bracelet and buckle.
  • Warranty Valid Until: October 2029
  • Size: 39mm
Posted at
Oct 16, 2025, 5:22 PM
Active
[WTS] Longines Hydroconquest 41

Longines Hydroconquest 41

Longines - L3.781.4.05.6 · $1,380
The Longines Hydroconquest 41 features a black dial and green ceramic bezel, comes with full kit, box, papers, warranty, and original purchase receipt.

  • Condition: essentially unworn
  • Shipping: CONUS only
Posted at
Oct 15, 2025, 8:12 PM
Active
[WTS] BNIB Longines HydroConquest

BNIB Longines HydroConquest

The Longines HydroConquest is a stylish and functional dive watch designed for everyday wear. It features a stainless steel case with a sleek design and a water-resistant construction.

  • Condition: Brand new in box (BNIB)
Posted at
Oct 15, 2025, 7:10 PM
Active
Longines HydroConquest, L3.781.4.06.9, Steel Diver, Olive, Excellent Condition.

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
Active