Rolex · Datejust 31

Strap for Datejust 31 Stainless Steel Diamond / Oyster / MOP

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
Reference178384-0018
FamilyDatejust 31
MovementRolex caliber 2235 hours, minutes, seconds | date | chronometer
CaseMother of Pearl | White Gold, Stainless Steel

Spring bar

Spring bars for Rolex

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

Straps for the Datejust 31 178384-0018

Selected for the 16 mm lug width

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The Datejust 31 178384-0018, seen from the bench

The Datejust 31 represents the female version of the Rolex Datejust collection, characterized by the 31mm diameter case. It is powered by the automatic caliber 2235 with hour, minute, second and date functions, certified as a chronometer. The lugs measure 16mm in width for the strap accommodation.

Frequently asked questions

What is the lug width of the Rolex Datejust 31 178384-0018?

The Rolex Datejust 31 reference 178384-0018 features a lug width of 16 millimetres. This dimension is standard across all Datejust 31 models and represents the optimal proportion between the 31mm case diameter and overall visual balance. To verify the measurement, position a digital calliper between the two lateral lugs on the case.

Which strap is most suitable for the Datejust 31 178384-0018?

For the Datejust 31 178384-0018 in white gold and stainless steel, the most coherent choices are black or dark brown alligator leather, which emphasises metallic restraint and showcases the mother-of-pearl dial. Vegetable-tanned calf leather offers an elegant alternative and develops a unique patina over time. For versatile wear, a black rubber or NATO strap in 16mm width permits quick changes whilst maintaining proportional harmony.

How do I change the strap on my Rolex Datejust 31?

The strap on the Datejust 31 178384-0018 is changed by removing the two spring bars connecting the lugs to the case. Use a dedicated tool (spring bar tool) to gently compress the internal spring whilst extracting the bar. Repeat on the opposite side. Insert the new 16mm strap by aligning the lug holes with the spring bars and reinsert the bars until they click into place. This operation is recommended at a qualified jeweller to avoid damage to the case.

Can I fit an aftermarket strap of quality on a Datejust 31 178384-0018?

Yes, any aftermarket strap with a 16mm lug width is compatible with the Datejust 31 178384-0018. A quality hand-crafted leather strap in alligator or calf is a legitimate choice and does not void Rolex warranty. We recommend manufacturers that guarantee construction quality and finishing consistent with Rolex standards, including stainless steel 316L spring bars and absence of adhesives.

How long does a leather strap last on a Datejust 31?

A quality leather strap (alligator, calf, shell cordovan) on a Datejust 31 178384-0018 typically lasts: 3-4 years with intense daily use, 5-7 years with moderate use, up to 10+ years with rotation and proper maintenance. Longevity depends on humidity exposure, perspiration, frequency of wear and periodic cleaning. A wet strap should be air-dried promptly. Vegetable-tanned finishes age naturally whilst developing patina; dyed alligator maintains more static colour.

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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