Longines · Conquest Heritage

Strap for Conquest Heritage 40mm Yellow Gold

Takes 20 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.

Lug width20 mm
Case diameter40 mm
ReferenceL1.645.6.75.4 (aka: L16456754)
FamilyConquest Heritage
MovementLongines caliber L633.5 Hours, Minutes, Seconds | Date
CaseYellow Gold

Spring bar

Swiss Standard universal spring bars

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

Straps for the Conquest Heritage L1.645.6.75.4 (aka: L16456754)

Selected for the 20 mm lug width · workshop selection

All 20 mm straps →

The Conquest Heritage L1.645.6.75.4 (aka: L16456754), seen from the bench

The Conquest Heritage represents the modern reinterpretation of a classic Longines model from the 1950s. It features the L633.5 caliber with hours, minutes, seconds, and date indication. The case has refined finishes with a crown and pushers that recall the original design of the era.

Frequently asked questions

What is the lug width of the Longines Conquest Heritage L1.645.6.75.4?

The Longines Conquest Heritage L1.645.6.75.4 features a lug width of 20 millimetres. This dimension, measured internally between the two case lugs, determines strap compatibility. You can verify it by placing a digital calliper perpendicularly between the upper lug attachments.

Which strap is most recommended for the Longines Conquest Heritage L1.645.6.75.4?

For this yellow gold model, an alligator strap with medium grain represents the optimal choice. The natural crocodile texture dialogues elegantly with gold, creating sophisticated light interplay. A vegetable-tanned calf strap in brown or cognac offers formal versatility with natural ageing patina.

How do you change the strap on the Longines Conquest Heritage L1.645.6.75.4?

Strap replacement is achieved by removing the pins that connect the strap to the case. Use a dedicated spring bar tool extractor to avoid damage. Position the new strap, ensuring the pins are correctly aligned and fully seated. Never force the case to prevent compromising the lugs.

Can I use an aftermarket compatible strap on my Longines Conquest Heritage L1.645.6.75.4?

Absolutely yes. The 20 millimetre lug width allows compatibility with quality artisanal straps. On milanostraps.it you will find numerous options in alligator, calf, shell cordovan and textiles, all tested for mechanical compatibility and comfort.

How long does a leather strap last on the Longines Conquest Heritage L1.645.6.75.4?

Durability depends on material and usage. A quality alligator strap can last 5-7 years with regular maintenance. Vegetable-tanned calf naturally ages over 3-5 years. Factors such as perspiration, sun exposure and frequency of use significantly affect longevity.

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