Rolex · Datejust 31

Strap for Datejust 31 Stainless Steel Domed / Jubilee / Blue Roman

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
Reference178240-0037
FamilyDatejust 31
MovementRolex caliber 2235 hours, minutes, seconds | date | chronometer
CaseStainless Steel

Spring bar

Spring bars for Rolex

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

Straps for the Datejust 31 178240-0037

Selected for the 16 mm lug width

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The Datejust 31 178240-0037, seen from the bench

The Datejust 31 represents the female version of the Rolex Datejust collection, with a 31mm diameter case. It is powered by the automatic Calibre 2235 with chronometer certification and displays of hours, minutes, seconds and date. The lugs measure 16mm in width for strap insertion.

Frequently asked questions

What is the lug width of the Rolex Datejust 31 ref. 178240-0037?

The Datejust 31 178240-0037 features a 16-millimetre lug width. This measurement corresponds to the space between the lug terminals where the strap attaches. Measuring accurately is essential before ordering a replacement strap to ensure perfect compatibility without play.

Which strap material is most suitable for the Datejust 31 178240-0037?

For a Datejust 31 in stainless steel, natural alligator leather remains the most aesthetically congruous choice — its organic grain enhances the case's visual clarity. Shell cordovan develops extraordinary patina over time. For daily resilience, vegetable-tanned calf offers versatility. Navy or grey NATO adds contained sportiness without destabilising the proportions of the 31mm case.

How do I change the strap on the Rolex Datejust 31 178240-0037?

You require a spring bar removal tool and well-lit working space. Position the watch horizontally, locate the small hole beneath the lug, insert the tool to compress the internal spring and extract the bar. Repeat for both sides. The new strap attaches simply: thread it through the lug and allow the spring to resume position. Without haste, the operation takes three minutes.

Can I fit an aftermarket strap to this Datejust 31?

Absolutely, provided it respects the 16mm lug width specification. Artisanal leather straps of superior quality to Rolex originals exist, particularly in vegetable-tanned alligator or shell cordovan. Compatibility is guaranteed by lug width, not by brand. A refined personalised strap elevates daily experience of your Rolex.

What is the typical lifespan of a leather strap for this watch?

Premium leather strap (alligator, shell cordovan) with daily wear lasts 3-5 years before replacement becomes necessary — not catastrophic degradation, but natural fibre wear at the lug collar due to continuous flexing. Original Rolex rubber surpasses five years. Lifespan depends on sunlight exposure, leather hydration and intensity of use. Maintenance: dry after fresh water contact, avoid perfumes.

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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