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 L3.781 — Modern Tool Diver (2025)

Longines - L3.781.4.566 · $999

A clean and modern 41mm diver that balances daily wearer and tool-watch capability, featuring a black dial and ceramic bezel.

Condition: Good, showing light signs of wear
Case size: 41 mm diameter
Water resistance: 300 m depth rating
Movement: Longines L888 caliber, automatic

Posted at

May 23, 2026, 11:01 AM

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Longines HydroConquest 44mm Black Dial Automatic

Longines - L3.841.4.56.6 · $800

Classic everyday dive watch with a clean black dial, automatic movement and 300m water resistance, perfect for daily wear.

Condition: Good overall
Case size: 44mm
Movement type: Automatic
Bezel material: Aluminum

Posted at

May 22, 2026, 6:21 PM

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Longines Hydroconquest 43mm

Longines - L3.782.4.56.6 · $1,240

The watch is a Longines Hydroconquest model L3.782.4.56.6 with a black dial and a 43mm case size.

Condition: Brand new with minor use (about a month)
Case size: 43mm diameter
Lug to lug length: 53mm
Thickness: 11.90mm

Posted at

May 22, 2026, 4:14 PM

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(brand new) Longines HydroConquest 39mm - $1700 shipped

Longines - HydroConquest · $1,700

This brand new Longines HydroConquest features a 39mm stainless steel case with black dial and ceramic bezel insert, along with a date display at the 3 o'clock position.

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

Posted at

May 21, 2026, 8:02 PM

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Longines hydroconquest 39 mm green

Longines - hydroconquest 39 mm green · $1,995

This Longines HydroConquest is a recent purchase from a US authorized dealer, still in its original packaging and with all papers.

Condition: great condition
Bracelet condition: has a small ding on the clasp
Box and paper status: all included
Additional strap type: aftermarket rubber

Posted at

May 21, 2026, 9:48 AM

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Longines HydroConquest 39mm Blue – Full Set – Excellent Condition

Longines - HydroConquest 39mm Blue · $1,900

This Longines HydroConquest is a 39mm watch with an automatic movement and ceramic bezel, featuring a blue dial and bezel.

Condition: Excellent Condition
Case size: 39mm diameter

Posted at

May 21, 2026, 4:05 AM

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[WTS] RARE CONFIGURATION Longines HydroConquest 42mm | 2026 Gen | Green Ceramic | Green Lacquered Dial | Ref. L3.788.4.06.6 | Never Worn | Full Kit | Warranty Card 5/8/26

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

Longines - L3.788.4.06.6 · $2,285

This is a rare configuration Longines HydroConquest 42mm watch with a green ceramic bezel and a green lacquered dial. It features an automatic movement, 300m water resistance, and a full kit including the original box, papers, and warranty card.

Condition: never worn
Bracelet: upgraded Longines mesh style bracelet
Movement: Calibre L888.5, automatic, silicon balance spring, 72hr power reserve
Water Resistance: 300m / 30 bar

Posted at

May 20, 2026, 3:53 PM

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