Strap for Datejust 31 Stainless Steel Diamond / Jubilee / Purple - Roman

The Rolex Datejust 31 ref. 178384-0013 features a lug width of 16mm. This measurement is specific to the 31mm case diameter and determines compatibility with aftermarket straps. To verify it, measure the internal distance between the two lugs at the case with a pair of digital callipers.

For the Datejust 31 in white gold and steel, hornback alligator or vegetable-tanned calf leather straps are the most coherent choices with the watch's level of craftsmanship. Alligator in midnight blue or anthracite grey enhances the nobility of the case without overpowering it; calf leather develops a natural patina over time that complements the mixed finishing of the case.

To replace the strap on the Datejust 31, a precision spring bar tool is required to remove the 16mm spring bars connecting the strap to the lugs. It is advisable to work on a soft surface to protect the case, and for first-time operations, to consult a professional watchmaker or a specialist atelier such as Casati Milano.

Yes, numerous artisanal manufacturers produce aftermarket straps with a 16mm lug width compatible with the Datejust 31. Milano Straps offers a selection of leather, NATO and technical material straps specifically dimensioned for the 16mm lug, with buckles and deployant clasps in steel or precious metals that maintain aesthetic coherence with the original case.

The lifespan of a leather strap depends on the material and care: a quality alligator strap, properly maintained and not systematically exposed to water, lasts on average 3–5 years with daily wear. Vegetable-tanned calf leather can reach 2–4 years while developing patina. Shell cordovan, owing to its compact fibre structure, is among the most durable materials and can last 5–7 years with adequate maintenance.