Rolex
Datejust 31 178273-0091— lug 16mm

The Rolex Datejust 31 reference 178273-0091 has a lug width of 16mm. This measurement should be taken internally between the two lugs using a digital calliper placed at the point where the strap sits, not across the external lug projection, which would give a reading 1-2mm too wide.

Given the yellow Rolesor two-tone case of the 178273-0091, the most suitable materials are alligator in havana or dark brown tones, vegetable-tanned calfskin that develops a personal patina over time, and anthracite vulcanised rubber for everyday wear. A steel or gold-tone deployant clasp is recommended to complement the mechanical character of the calibre 2235.

To replace the strap on the Datejust 31, use a fine-tipped spring bar tool or a precision screwdriver to remove the 1.5mm diameter spring bars housed in the lugs. Work on a soft cushion to avoid scratching the case and ensure the replacement spring bar length is approximately 16.5-17mm, compatible with the internal width of Rolex lugs.

Yes. Several artisan manufacturers, including Casati Milano, produce aftermarket straps specifically for 16mm lug widths compatible with the Datejust 31. It is essential to request straps with straight (not curved) ends, a 16mm attachment width, and 1.5mm diameter spring bars to ensure correct fitting in the original Rolex lugs without forcing.

Longevity depends on the material and frequency of use. A quality alligator strap, with regular use and proper care (avoiding prolonged moisture, applying protective cream every 2-3 months), typically lasts 3-5 years. Vegetable-tanned calfskin has a similar lifespan but develops a personal patina that many consider an asset. Casati Milano offers an 18-month guarantee against manufacturing defects on all its straps.