Longines HydroConquest Hydroconquest Chronograph L688

Reference L3.696.4.13.6

About this watch

The Longines Hydroconquest Chronograph L688 is a masterpiece of luxury watchmaking that seamlessly blends functionality, style, and heritage. This Swiss-made timepiece boasts an impressive array of features, including a robust stainless steel case with a silver dial, Arabic numerals, and proprietary hands designed for maximum readability. The rotating bezel, with its 0-60 scale, is a functional piece of art that's perfect for measuring elapsed time while diving or engaging in other time-critical activities. At the heart of this watch lies the Longines caliber L688.2, an automatic movement that offers precision and reliability, with a frequency of 28,800 vibrations per hour and a power reserve of 54 hours. With its impressive water resistance of up to 300 meters, this watch is built to withstand the elements, making it perfect for both land-lovers and divers alike. Its sleek aesthetics and refined elegance make it suitable for any occasion, from casual to formal settings.

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Key Features

Longines caliber L688.2 automatic movement
Rotating bezel with 0-60 scale
Stainless steel case with silver dial
Arabic numerals and proprietary hands
Water resistance up to 300 meters
Sapphire crystal glass
41.00 mm diameter

Specifications

Brand

Longines

Family

HydroConquest

Model

Hydroconquest Chronograph L688

Reference

L3.696.4.13.6

Movement

l688-2

Movement Features

Hours, Minutes, Small Seconds
Date
Chronograph, Column wheel

Case

Stainless Steel 41mm

Dial Color

Silver

Crystal

Sapphire

Water Resistance

300

Current Listings

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 43mm Full Black Ceramic Ref L3.784.4.56.9 MINT Full Kit $2500

Longines - L3.784.4.56.9 · $2,500

This Longines HydroConquest features a unique full black ceramic aesthetic with a sleek and stealthy design, while maintaining refined and versatile qualities. The watch boasts excellent scratch resistance, legible dial, and comfortable daily wear.

Condition: MINT
Case diameter: 43mm
Thickness: 13mm
Lug-to-lug length: 56mm

Posted at

Apr 10, 2026, 8:26 PM

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Longines Hydroconquest GMT | 41mm | Sunburst Brown | Excellent Condition

Longines - Hydroconquest GMT · $1,350

This Longines Hydroconquest GMT is a refresh of the well-loved hydroconquest line range, featuring a new quick-adjust bracelet and updated bezel with brown ceramic insert. The sunray dial looks incredible in all lighting conditions, especially when exposed to sunlight.

Condition: Excellent
Case size: 41mm diameter
Lug to lug: 49.2mm
Thickness: 12.8mm

Posted at

Apr 8, 2026, 5:34 PM

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Longines HydroConquest 2 tone Green Dial 2024 $1320

Longines - HydroConquest 2 tone Green Dial 2024 · $1,320

Image: https://imgur.com/a/bPjxHRP

Posted at

Apr 7, 2026, 9:36 AM

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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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