Rolex · Datejust 31

Strap for Datejust 31 Yellow Gold / Fluted / Malachite / President

Takes 16 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.

Lug width16 mm
Case diameter31 mm
Reference278278-0004
FamilyDatejust 31
MovementRolex caliber 2236 hours, minutes, seconds | date | chronometer
Year2018
CaseYellow Gold

Spring bar

Spring bars for Rolex

The right category for this model · choose the 16 mm size

Straps for the Datejust 31 278278-0004

Selected for the 16 mm lug width

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The Datejust 31 278278-0004, seen from the bench

The Datejust 31 reference 278278-0004 is equipped with the automatic caliber 2236 with hour, minute, second and date functions, certified as a chronometer. The 31mm case has 16mm lug width. The movement provides date indication in addition to the chronometric time display.

Frequently asked questions

What is the exact lug width of the Rolex Datejust 31 278278-0004?

The lug width of the Rolex Datejust 31 278278-0004 is 16 millimetres. This measurement represents the internal spacing between the two lugs on the case where the strap is attached. To verify it accurately, measure the perpendicular distance between the two metal lugs using a digital calliper: it must be precisely 16mm. Measuring correctly is essential to avoid purchasing incompatible straps.

Which strap material is most suitable for the yellow gold Datejust 31 278278-0004?

For the Rolex Datejust 31 278278-0004 in yellow gold, alligator remains the traditional aesthetic choice: its fine grain and naturally developed patina express pure luxury. Shell cordovan offers superior robustness and intrinsic lustre. Vegetable-tanned calf leather suits those seeking daily versatility whilst maintaining elevated construction standards. Recommended colours: dark brown, charcoal grey, optical black, navy blue.

How do you change the strap on a Rolex Datejust 31 without damaging the case?

Changing the strap on a Rolex Datejust 31 requires a spring bar tool and delicate movements. Insert the flat tip of the tool into the lateral grooves of the spring bar, working gently inward. Once one end is released, extract the bar. Repeat on the opposite side. Insert the new spring bar into the lugs, clicking until fully secured. If you lack experience, consult a specialised watchmaker to avoid scratching the gold case.

Is an aftermarket 16mm strap truly compatible with the Rolex Datejust 31?

Yes, an aftermarket strap with a 16mm lug width is mechanically compatible with the Rolex Datejust 31 278278-0004. However, mechanical compatibility does not guarantee aesthetic coherence. Select straps from craftsmen who understand Rolex proportions: thickness, stitching, colour and patina must harmonise with the gold case. A bulky or poorly finished strap betrays the watch's quality. Relying on specialists ensures visual harmony.

How long does a leather strap last on a daily-worn Rolex?

A high-quality alligator strap, with authentic leather and appropriate tanning, typically lasts 4–6 years of daily use before showing significant wear. Shell cordovan, thanks to its natural density, can endure 6–8 years. Calf leather, less dense, wears in 2–4 years. Longevity depends on climate (humidity stresses leather), frequency of sweat contact, and the strap's construction quality. Regular maintenance (gentle cleaning with a damp cloth) significantly extends lifespan.

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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