Rolex
Datejust 31 178248-0023— lug 16mm

The Rolex Datejust 31 ref. 178248-0023 has a lug width of 16 mm. This measurement should be taken with a digital calliper between the inner surfaces of the lugs, parallel to the case. It is essential not to approximate to adjacent sizes: a 17 mm strap would create lateral play, whilst a 15 mm strap would not fit correctly within the lugs.

For the Datejust 31 in yellow gold, an alligator strap with vegetable tanning offers the most coherent stylistic pairing: the hornback or belly grain complements the polished surfaces of the precious metal lugs. Alternatively, polished box-calf leather provides a similarly formal register with a personalised patina developing over time. For a less formal daily-wear approach, shell cordovan in cognac or tobacco tones delivers durability and a distinctive aesthetic character.

To replace the strap on the Datejust 31, a fine-tip double-ended springbar tool is required to remove the springbars from the 16 mm lugs. Insert the tip into the lug slot, compress the springbar and slide the strap free. Care must be taken to avoid scratching the yellow gold lugs: it is advisable to protect the case with microporous tape during the operation, or to entrust the work to a watchmaker or the Casati Milano atelier.

Yes. The Datejust 31 ref. 178248-0023 accepts any strap with a 16 mm lug width and a straight or curved end compatible with the geometry of Rolex lugs. Milano Straps offers a selection of handcrafted 16 mm straps in various materials — alligator, calf, shell cordovan, rubber — manufactured to ensure a precise fit and lasting durability, without any modification to the original watch.

The lifespan of a leather strap depends on the material and frequency of use. A quality vegetable-tanned alligator strap, used in rotation with other straps, can last between 3 and 5 years whilst developing a fine patina. Calf leather tends to show signs of wear sooner, particularly in humid climates. Shell cordovan, owing to the density of its fibres, offers the greatest structural resistance over time. Regular conditioning with a neutral leather cream every 2–3 months significantly extends the strap's service life.