Strap for Datejust 31 Stainless Steel / Yellow Gold / Diamond / Grey - Roman / Jubilee

The Rolex Datejust 31 ref. 278383rbr-0018 has a lug width of 16mm. This measurement is specific to the 31mm Datejust models and differs from the 20mm found on the Datejust 41 or Submariner. Always verify with a digital calliper positioned inside the lugs before purchasing a replacement strap.

For this steel and yellow gold reference, the most suitable straps are smooth alligator in warm tones (chocolate, cognac) or shell cordovan for intensive daily wear. Vegetable-tanned calf leather is ideal for those seeking a natural patina over time. For sport or outdoor use, an anatomical rubber strap in 16mm ensures proper fit and water resistance.

To replace the strap, a 1.2mm springbar tool is required to remove the spring bars from the lugs. Exercise caution to avoid scratching the polished steel lug surfaces. If you have not performed this operation before on a Rolex, it is advisable to entrust the task to a watchmaker or specialist atelier to prevent damage to the case finishing.

Yes, high-quality aftermarket straps are made specifically for the 16mm lug width. Milano Straps offers a curated selection of handcrafted straps in alligator, calf leather, and shell cordovan, fitted with steel buckles or deployant clasps. The full range is available at milanostraps.it in the dedicated 16mm strap section.

Longevity depends on the material and conditions of use. A quality alligator strap, maintained with leather conditioner every 3–4 months and kept away from prolonged moisture exposure, typically lasts 3–5 years with daily wear. Shell cordovan offers superior durability and may exceed 5 years. Vegetable-tanned calf leather is more sensitive to humidity but develops a distinguished patina. Casati Milano straps carry an 18-month warranty against manufacturing defects.