Rolex · Datejust 31

Strap for Datejust 31 Stainless Steel/ Rose Gold / Diamond / Rose / 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
Reference278381rbr-0009
FamilyDatejust 31
MovementRolex caliber 2236 hours, minutes, seconds | date | chronometer
Year2018
CaseRose Gold, Stainless Steel

Spring bar

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Straps for the Datejust 31 278381rbr-0009

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The Datejust 31 278381rbr-0009, seen from the bench

The Rolex Datejust 31 ref. 278381rbr-0009 is a 31mm mid-size model combining Everose gold—Rolex's proprietary platinum-enriched alloy—with Oystersteel 904L and diamond-set bezel. The caliber 2236 movement is COSC-certified and regulated to Rolex Superlative Chronometer standards (±2 seconds/day), featuring a Syloxi silicon hairspring for magnetic resistance. The case diameter sits between the 28mm Lady-Datejust and 36mm classic Datejust. The 16mm lug width is specific to all 31mm Datejust models and is not interchangeable with 36mm (20mm) or 28mm (13mm) versions.

Frequently asked questions

What is the lug width of the Rolex Datejust 31 278381rbr-0009?

The lug width of the Rolex Datejust 31 ref. 278381rbr-0009 is 16mm. This measurement is taken between the two lugs at the narrowest point closest to the case, and is the key parameter for selecting any compatible replacement strap.

What is the best strap for the Rolex Datejust 31 278381rbr-0009?

For this reference in Everose gold and Oystersteel with a diamond-set bezel, a vegetable-tanned alligator strap is the most coherent match both aesthetically and in terms of quality. Box-calf leather is the most versatile option for everyday wear, while a nylon NATO strap suits informal settings. Recommended colours include bordeaux, tobacco brown, or midnight blue.

How do you change the strap on a Rolex Datejust 31 278381rbr-0009?

The strap is removed using a fine-tipped spring bar tool or a micro-screwdriver. The 16mm spring bars are compressed laterally to release the lugs. Although straightforward in principle, care must be taken not to scratch the Everose gold lugs; it is advisable to protect the case with low-tack adhesive tape during the operation.

Are there aftermarket straps compatible with the Rolex Datejust 31 278381rbr-0009?

Yes. Any strap with a 16mm lug width and standard spring bars is technically compatible with the Datejust 31 278381rbr-0009. Milanostraps.it offers handcrafted straps in alligator, calf leather, shell cordovan, and nylon specifically made for this width, with buckles and deployant clasps in steel or rose gold PVD to complement the original case.

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

Longevity depends on the material and level of care. A quality alligator strap, conditioned with leather cream every 3–4 months and stored away from direct moisture, will maintain its structural and aesthetic integrity for 3–5 years of regular use. Shell cordovan, being denser, tends to last longer and develops a distinctive patina over time. Prolonged exposure to perspiration and UV light is the primary cause of premature deterioration.

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