Rolex
Datejust 31 178384-0059— lug 16mm

The Rolex Datejust 31 ref. 178384-0059 has a lug width of 16mm. This measurement is taken with a calliper at the inner distance between the two lugs, level with the caseback. It is a specific dimension requiring straps built to this exact width to ensure a clean fit and consistent aesthetic finish.

For the Datejust 31 in white Rolesor, an alligator strap in vegetable-tanned leather with a semi-gloss finish is the most coherent choice: the scale grain complements the reflections of the white gold. Alternatively, box calf leather offers a refined everyday register, while shell cordovan develops a distinguished patina over time. For summer or active use, vulcanised rubber maintains water resistance without compromising on style.

To replace the strap on a Rolex Datejust 31, you will need a quality spring bar tool with a protected tip to avoid scratching the white gold or steel lugs. Compress the spring bar, slide out the pin and fit the new strap. It is advisable to work on a soft surface under good lighting. If in doubt, Casati Milano offers an in-atelier strap fitting service.

Yes. Aftermarket straps with a 16mm lug width and shaped ends to follow the curvature of Rolex lugs are fully compatible with this reference. Milanostraps.it offers a curated selection of handcrafted 16mm straps in alligator, calfskin, shell cordovan and rubber, fitted with standard 1.8mm spring bars compatible with the original Datejust 31 lugs.

The lifespan of a leather strap depends on the material, care and intensity of use. A quality vegetable-tanned alligator strap, worn daily but protected from water and excessive perspiration, typically lasts 2 to 4 years before replacement is needed. Shell cordovan, being denser and less porous, tends to last longer while developing a noble patina. Casati Milano provides an 18-month warranty against manufacturing defects on all straps.