Rolex · Datejust 31

Strap for Datejust 31 Yellow Gold / Fluted / Butterfly / Oyster

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
Reference278278-0021
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 278278-0021

Selected for the 16 mm lug width

All 16 mm straps →

The Datejust 31 278278-0021, seen from the bench

The Rolex Datejust 31 reference 278278-0021 is a 31mm watch in solid 18-carat yellow gold with a fluted bezel and Oyster case, water-resistant to 100 meters. It features the Rolex caliber 2236, an automatic movement with silicon Syloxi oscillator, COSC-certified chronometer precision, and approximately 55 hours power reserve. The 16mm lug width is a non-standard dimension requiring careful strap selection for replacement.

Frequently asked questions

What is the lug width of the Rolex Datejust 31 reference 278278-0021?

The Rolex Datejust 31 ref. 278278-0021 features a lug width of 16mm. This non-standard measurement — compared to the more common 18mm or 20mm — requires careful selection of any replacement strap. It is advisable to verify the lug width with a digital calliper before purchasing a strap.

What is the best strap for the Rolex Datejust 31 278278-0021?

For the yellow gold case of the Datejust 31, alligator leather with a gloss finish and shell cordovan are the most suitable choices for formal settings, as their texture and natural patina complement the precious metal. For everyday wear, vegetable-tanned calf leather offers both comfort and refinement. The recommended closure is a yellow gold pin buckle or a butterfly deployant clasp at 16mm.

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

To replace the strap on the Datejust 31, a suitable spring bar tool or thin-tipped lever is required. The spring bars connecting the strap to the case lugs must be carefully removed to avoid scratching the gold surface. It is recommended to work on a soft watchmaker's mat and, if in doubt, to entrust the operation to a professional watchmaker or the Casati Milano atelier.

Are there aftermarket straps compatible with the Rolex Datejust 31 ref. 278278-0021?

Yes. Milano Straps manufactures handcrafted straps compatible with the 16mm lug width of the Datejust 31. Available models include alligator, shell cordovan, vegetable-tanned calf leather and rubber, with bespoke stitching and finishing. Each strap is produced to match the original Rolex lug geometry for a precise and secure fit.

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

The lifespan of a leather strap depends on the material, frequency of use and wearing conditions. A high-quality alligator or shell cordovan strap, kept away from excessive moisture and perspiration, can last between 3 and 7 years while developing a distinguished patina. Milano Straps products are covered by an 18-month guarantee against manufacturing defects.

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