Rolex
Datejust 31 278383rbr-0026— lug 16mm

The Rolex Datejust 31 ref. 278383rbr-0026 has a lug width of 16mm. To confirm this, measure the internal distance between the two lower lugs using a digital calliper. This dimension is specific to the 31mm case and requires straps with a 16mm attachment.

For this Oystersteel and yellow gold version with a diamond-set bezel, an alligator strap in vegetable-tanned leather — in cognac brown or black — is the most coherent choice given the character of the dial. Alternatively, polished box-calf leather offers a more understated register, while FKM rubber is recommended for sport or summer use.

Strap replacement requires a 1.0–1.2mm spring bar tool or a dedicated lever. Remove the two spring bars securing the strap to the lugs. Work on a soft surface and ensure the spring bars are correctly aligned before inserting them into the lug holes, to avoid scratching the yellow gold case.

Yes. Any strap with a standard 16mm attachment and spring bars is compatible. Milano Straps manufactures bespoke straps for this reference in alligator, calf leather, NATO and rubber. It is essential to respect the 16mm lug width to ensure a correct, force-free fit.

Longevity depends on the material and maintenance. A quality vegetable-tanned alligator strap, worn regularly but not in intensive daily conditions, retains its structural and aesthetic integrity for 3–5 years. Prolonged exposure to perspiration, water and UV light accelerates deterioration. Regular conditioning with a neutral cream and rotating between multiple straps will significantly extend the strap's service life.