Strap for Datejust 31 Stainless Steel Domed Diamond / Jubilee / Bronze - Roman

The Rolex Datejust 31 ref. 178344-0001 has a lug width of 16mm. This measurement must be taken with a digital calliper at the inner gap between the case lugs. It is a non-standard size compared to more common widths such as 18mm or 20mm, so it is essential to select straps specifically rated for 16mm lug width to ensure correct fitting and avoid mechanical stress on the lugs.

For the bi-metal white gold and steel Datejust 31, a vegetable-tanned alligator strap is the most coherent choice in keeping with the watch's positioning. Recommended colours include midnight blue, burgundy, slate grey, or black for dark dials. Smooth European calfskin is a more casual everyday alternative. Vulcanised rubber suits sporting contexts. In all cases, the strap width must be exactly 16mm at the lug end.

To replace the strap on the Datejust 31, a spring bar tool is required to release the spring bars housed in the lug holes on either side of the case. It is advisable to work on a soft surface to prevent scratches to the caseback. If you are unfamiliar with the process, it is preferable to consult a watchmaker or the Casati Milano atelier, where strap fitting is included as part of the bespoke service.

Yes. The Rolex Datejust 31 ref. 178344-0001 accepts any aftermarket strap with a 16mm lug width and standard spring bars. Milano Straps offers a curated selection of compatible handcrafted straps available online, in alligator, calfskin, NATO, and rubber. For a bespoke solution with direct leather selection, Casati Milano operates by appointment with an 18-month production warranty.

The lifespan of a leather strap depends on the quality of the tanning, the type of hide, and daily care. A high-quality vegetable-tanned alligator strap, handled with care — avoiding prolonged exposure to water, perspiration, and direct sunlight — can last between 3 and 6 years while retaining its structure and developing a distinguished patina. Calfskin tends to wear more quickly, particularly at the flex point. Alternating between two straps significantly extends the life of both.