Rolex
Datejust 31 178384-0011— lug 16mm

The lug width of the Rolex Datejust 31 ref. 178384-0011 is 16mm. This measurement is specific to the 31mm case and differs from the 20mm lug width of the Datejust 36. To verify it accurately, use a calliper to measure the internal distance between the lugs at the point where the strap attaches.

For the Datejust 31 in steel and white gold, alligator leather with a polished finish is the most aesthetically coherent choice: the regular belly grain echoes the fluted bezel. Alternatively, vegetable-tanned calf leather develops a natural patina over time, while shell cordovan offers exceptional durability and character. For sporting use, a vulcanised rubber strap with a steel deployant clasp is the most functional option.

To replace the strap on the Datejust 31, a spring bar tool suited to Oyster lugs is required. Insert the tip of the tool into the dedicated notch on the side of the lug to compress the spring bar and release the strap. This is a reversible operation that does not require professional tools, though it is advisable to entrust the task to a watchmaker or atelier to avoid scratching the steel and white gold case.

Yes, there are numerous aftermarket straps with a 16mm lug width compatible with the Datejust 31. Milano Straps offers a selection of handcrafted leather, rubber and fabric straps specific to this lug size. It is essential to ensure that the strap is manufactured to a precise 16mm tolerance and that the buckle or deployant clasp is compatible with the watch's spring bars.

The lifespan of a leather strap depends on the material and daily use. A high-quality alligator or shell cordovan strap, with proper care — drying after exposure to moisture and periodic conditioning with a leather cream — can last between 3 and 7 years. Vegetable-tanned calf leather has an average lifespan of 2 to 4 years, developing a distinctive patina over time. A deployant clasp reduces mechanical wear, extending the life of the strap considerably.