Longines · HydroConquest

Strap for HydroConquest 43 Automatic Stainless Steel - Yellow Gold / Green / Rubber

Takes 21 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.

Lug width21 mm
Case diameter43 mm
ReferenceL3.782.3.06.9
FamilyHydroConquest
MovementLongines caliber L888.5 hours, minutes, seconds | date | chronometer
Year2022
CaseCeramic, Stainless Steel

Spring bar

Swiss Standard universal spring bars

The right category for this model · 316L steel, all lug widths 13–26 mm

Straps for the HydroConquest L3.782.3.06.9

Selected for the 21 mm lug width · workshop selection

All 21 mm straps →

The HydroConquest L3.782.3.06.9, seen from the bench

The Longines HydroConquest ref. L3.782.3.06.9 features the automatic caliber L888.5 with chronometer certification and functions of hours, minutes, seconds and date. The watch features 21mm lugs for the strap. This is a diving timepiece from the Swiss brand's sports collection.

Frequently asked questions

What is the lug width of the Longines HydroConquest L3.782.3.06.9?

The lug width of the L3.782.3.06.9 is 21mm. This is an intermediate size between the standard 20mm and 22mm, offering a good range of strap options. Measure internally at the spring bar passage with a digital calliper, ensuring the value is between 20.8 and 21.2mm for a fit without play.

Which strap is most suitable for the Longines HydroConquest L3.782.3.06.9?

For the L3.782.3.06.9 we recommend alligator straps with vegetable tanning for formal elegance, shell cordovan for those seeking natural patina development, or vegetable-tanned calf for everyday practicality. For actual diving use, high-quality vulcanised rubber with internal canvas passage ensures maximum durability in marine environments. Choice depends on the watch's primary use.

How do you change the strap on the Longines HydroConquest L3.782.3.06.9?

Position the watch with the caseback facing upward. Locate the spring bar beneath the lug. Use a spring bar tool to gently press the bar in one direction, releasing tension. Remove the old strap from the spring bar. Insert the new strap by aligning the passage with the spring bar, verify correct positioning, and release. Never force the strap; if resistance occurs, verify the width is genuinely 21mm.

Are there aftermarket straps compatible with the Longines HydroConquest L3.782.3.06.9?

Yes, many high-quality aftermarket straps are compatible with the 21mm lug width. Milano Straps offers a dedicated collection of 21mm artisanal leather straps. Always verify that the passage width is exactly 21mm before purchase by precise measurement.

How long does a leather strap last on the Longines HydroConquest L3.782.3.06.9?

Durability depends on leather quality and use. A high-quality artisanal alligator or shell cordovan strap lasts 4-6 years with ordinary care (avoid repeated wetting, constant humidity, prolonged sweat). Vegetable-tanned calf has slightly shorter duration, 3-5 years. Vulcanised rubber lasts 5-8 years if not exposed to intense UV. The 18-month guarantee from Casati Milano covers manufacturing defects during this period.

The next step

The right strap isn't chosen. It is built, together.

From the atelier appointment to delivery, every step is made for those who know that things done well take time. Rare leathers, one piece at a time, eighteen months of warranty.

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Casati Milano · Via XX Settembre 15, Milan · by appointment only