Strap for Datejust 31 Yellow Gold / Diamond / Malachite / President

The lug width of the Datejust 31 278288rbr-0004 is 16 millimetres. This measurement represents the distance between the two horizontal pins that attach the strap to the case lugs. To verify this on your own watch, use a ruler or flexible measuring tape and measure the distance between the centre of the right pin and the centre of the left pin.

For a yellow gold Datejust 31, an alligator strap in dark brown or cognac tones is the ideal choice, as it enhances the warmth of the gold. Refined alternatives include vegetable-tanned calf leather, shell cordovan for superior durability, or a NATO in neutral shades such as anthracite grey for versatile daily wear. The choice depends on your intended use and personal style.

Strap replacement is performed by removing the two horizontal pins that connect the strap to the case lugs. Use a dedicated spring bar tool to gently extract the pins from either end, after which the strap can be removed easily. Insert the new strap by threading the pins through the lugs and ensure the strap is properly aligned. Alternatively, you may entrust a professional watchmaker or Casati Milano to perform the replacement service.

Yes, aftermarket straps compatible with the 16mm lug width are widely available. Milanostraps offers a dedicated collection of 16mm straps featuring materials such as alligator, calf leather, shell cordovan, and NATO. You can browse the full collection on the 16mm strap compatibility page. For a bespoke personalised strap, Casati Milano provides haute couture services by appointment.

The lifespan of a leather strap depends on the leather quality, tanning method, and daily use. A high-quality alligator or shell cordovan strap, worn daily with proper care, typically lasts 4–6 years before requiring professional restoration. Vegetable-tanned calf straps tend to show patina more quickly but acquire character through use. All Casati Milano artisanal straps carry an 18-month warranty against manufacturing defects and can be professionally restored to extend their life.