Rolex · Datejust 31

Strap for Datejust 31 Rolesor Yellow Diamond / Oyster / Black 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
Reference178383-0021
FamilyDatejust 31
MovementRolex caliber 2235 Hours, Minutes, Seconds | Date | Chronometer
CaseMother of Pearl | Yellow 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 178383-0021

Selected for the 16 mm lug width

All 16 mm straps →

The Datejust 31 178383-0021, seen from the bench

The Datejust 31 represents the feminine version of the Rolex Datejust collection. It is equipped with the automatic caliber 2235 with chronometer certification and display of hours, minutes, seconds and date. The case features 16mm lugs suitable for smaller sized straps.

Frequently asked questions

What is the lug width of the Rolex Datejust 31 178383-0021?

The Datejust 31 reference 178383-0021 features a lug width of 16 millimetres. This is the distance between the case lugs where the leather strap passes are fitted. Any aftermarket strap must be precisely 16mm wide to ensure perfect compatibility and secure attachment without play or stress on the case.

Which strap material is most recommended for the Rolex Datejust 31?

For the Datejust 31 178383-0021 in the Rolesor configuration (steel and yellow gold), we recommend straps in genuine alligator or premium calf leather. Alligator represents the most prestigious choice due to its distinctive texture and the patina it develops over time. Calf leather offers a versatile and durable alternative, ideal for those seeking formal aesthetics without the more delicate care that alligator requires.

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

To change the strap, you must remove the spring bars using a specialised spring bar tool. Position the watch so the lug is accessible, insert the tool into the small slot beneath the lug, apply gentle pressure to compress the internal spring and withdraw the bar. Repeat on the other side. Once the old strap is removed, insert the new spring bars into the lugs and ensure they are fully seated until you feel the click. If unsure, contact an authorised Rolex dealer or a qualified watchmaker.

Is a quality aftermarket strap compatible with the Datejust 31?

Yes, provided the strap is designed for the 16mm lug width. Milano Straps offers bespoke artisanal straps compatible with your Datejust 31 in various materials—alligator, calf, vegetable-tanned leather—available either made-to-order or from ready stock. What matters is verifying that the attachment points are precisely 16mm wide and that the material and style are coherent with your Rolex's aesthetic. A high-quality aftermarket strap can renew your wearing experience without compromising the value of the watch.

How long does a leather strap last on a watch like the Datejust 31?

The lifespan of a leather strap depends on material quality, frequency of use and maintenance. A premium alligator or calf strap, worn daily, may last 3-5 years before showing significant signs of wear. If worn occasionally, longevity extends easily to 7-10 years. Vegetable-tanned leather tends to be more fragile but develops a fascinating patina with age. Milano Straps offers an 18-month warranty against manufacturing defects and can provide support for periodic maintenance and strap renewal.

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.

Request an appointment →

Casati Milano · Via XX Settembre 15, Milan · by appointment only