Longines HydroConquest Hydroconquest Chronograph L688

Reference L3.696.4.53.6

About this watch

The Longines Hydroconquest Chronograph L688 is a statement piece that combines elegance with functionality. This robust diving watch features a stunning black dial, Arabic numeral indexes, and a rotating bezel for precise timing. Its 300-meter water resistance makes it perfect for underwater escapades. The automatic movement, powered by a column wheel chronograph system, ensures smooth and accurate operation. With a 54-hour power reserve, you can wear this watch without worrying about winding it every day. The stainless steel case is durable and polished, making it suitable for both formal events and casual wear. This watch is an investment that combines style, functionality, and heritage. Its rich history, impeccable craftsmanship, and versatile design make it a must-have for anyone who appreciates quality timepieces.

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Key Features

Automatic movement with 54-hour power reserve
300-meter water resistance for diving
Chronograph function for precise timing
Stainless steel case with polished finish
Rotating bezel for tracking elapsed time
Black dial with Arabic numeral indexes

Specifications

Brand

Longines

Family

HydroConquest

Model

Hydroconquest Chronograph L688

Reference

L3.696.4.53.6

Movement

l688-2

Movement Features

Hours, Minutes, Small Seconds
Date
Chronograph, Column wheel

Case

Stainless Steel 41mm

Dial Color

Black

Water Resistance

300

Current Listings

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 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, 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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View listing on RolexForums