Rolex
Datejust 31 178158-0078— lug 16mm

The Rolex Datejust 31 reference 178158-0078 features a lug width of 16mm. This measurement refers to the internal distance between the Oyster case lugs in 18ct yellow gold and determines compatibility with any aftermarket or original strap. Before purchasing a replacement strap, it is advisable to verify the measurement using a digital calliper placed inside the lugs, in contact with the spring bar attachment points.

For an 18ct yellow gold case such as that of the Datejust 31, the most suitable materials are Mississippiensis alligator in cognac or bordeaux tones, which harmonises with the warmth of the metal, and shell cordovan in dark brown, offering an elegant contrast. Tuscan Box Calf leather in burgundy or navy is the ideal choice for a more understated aesthetic. The correct width is 16mm with curved ends to ensure a precise fit within the Oyster case lugs.

To replace the strap on a Rolex Datejust 31, a spring bar tool or a 1.5mm replacement pin compatible with Rolex original spring bars is required. Insert the tool into the notch on the spring bar, compress the spring inward and slide the strap free from the lug. Care must be taken not to scratch the yellow gold case: it is advisable to protect the lugs with masking tape before proceeding, or to entrust the operation to a watchmaker or the Casati Milano atelier.

Yes. The Datejust 31 with 16mm lug width is compatible with all aftermarket straps manufactured in this size with curved ends. Milano Straps offers a selection of handcrafted straps in alligator, calf leather, shell cordovan and rubber specifically made for 16mm lugs, with bespoke tailoring available through the Casati Milano atelier. It is essential to ensure that the chosen strap features the correct curved ends to suit the geometry of the yellow gold Oyster case.

The lifespan of a leather strap on a Rolex Datejust 31 depends on the material, frequency of use and maintenance. A high-quality alligator strap, kept away from excess water and perspiration and treated periodically with a suitable leather conditioner, can last between 3 and 7 years whilst retaining its structural and aesthetic integrity. Shell cordovan, owing to its dense fibre structure, tends to last longer and develops a distinctive patina over time. Milano Straps straps are covered by an 18-month warranty against manufacturing defects.