Rolex · Datejust 31

Strap for Datejust 31 Stainless Steel Diamond / Jubilee / Blue

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
Reference178384-0029
FamilyDatejust 31
MovementRolex caliber 2235 Hours, Minutes, Seconds | Date | Chronometer
CaseWhite 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 178384-0029

Selected for the 16 mm lug width

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The Datejust 31 178384-0029, seen from the bench

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

Frequently asked questions

What is the lug width of the Rolex Datejust 31 reference 178384-0029?

The Rolex Datejust 31 reference 178384-0029 has a lug width of 16mm. This is a non-standard measurement compared to more common Rolex models; always verify the actual distance between the lugs with a digital calliper before purchasing an aftermarket strap.

What is the best strap for the Datejust 31 178384-0029?

For the Datejust 31 in white Rolesor, alligator belly straps in cool tones (grey, taupe, écru) or shell cordovan in burgundy offer the finest aesthetic balance. A deployant clasp in steel or white gold PVD is recommended for daily wear. Milano Straps offers a curated selection of handcrafted 16mm straps specifically suited to this reference.

How do you change the strap on a Rolex Datejust 31?

The strap is secured by 1.8mm springbars. Use a dedicated springbar tool — either fork-tip or pin-tip — applying pressure within the lug recess without touching the case surface. Work on a soft mat to avoid scratches, and if in doubt, consult a watchmaker or visit the Casati Milano atelier.

Are there aftermarket straps compatible with the Datejust 31 178384-0029?

Yes. Several artisan manufacturers produce straps with a 16mm lug width and an end-piece profile suited to the Datejust 31 lugs. Milano Straps offers a carefully selected range of leather, rubber and nylon straps with correctly profiled ends that fit the case without play or undue tension.

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

Longevity depends on the material and conditions of use. A quality alligator or shell cordovan strap, kept away from water, excessive perspiration and direct heat, typically lasts 2–4 years with daily wear. Vegetable-tanned calfskin develops a personal patina and offers comparable longevity if not regularly exposed to moisture. Milano Straps provides an 18-month warranty against manufacturing defects on all Casati Milano straps.

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