Strap for Datejust 31 Stainless Steel / Yellow Gold / Fluted / Silver - Roman / Oyster

The lug width (also called case lug width) of the Rolex Datejust 31 278273-0003 is 16 millimetres. This is a specific, non-standard measurement that determines compatibility with aftermarket straps. Lug width is measured as the internal distance between the two case lugs. Only straps with 16mm diameter spring bars will fit correctly on this model.

For a bicolour Datejust 31 278273-0003 Rolesor (steel and yellow gold), dark brown or black alligator straps are the most harmonious choice. Alternatively, vegetable-tanned calfskin in natural brown or satin black maintains elegance and develops authentic patina over time. For those preferring a sportier aesthetic, a cotton-and-silk NATO in grey or navy blue coordinates well with the steel component of the case.

Strap replacement requires specific tools: a Rolex case opener (pin remover) or a small flat-head screwdriver, a case holder, and patience. Position the watch securely, locate the spring bar pin that runs through the lug horizontally, and gently push the pin outward until it disengages completely. Repeat for the opposite lug. Remove the old strap and insert the new one, reinserting the spring bars through both lugs. We recommend entrusting this operation to a qualified watchmaker or Rolex service centre if you lack experience, to avoid scratching the case.

Yes. Aftermarket 16mm straps are available from specialists such as Milano Straps, which produces handcrafted leather straps in alligator, calfskin, and technical materials. Compatibility is guaranteed by the specific lug width (16mm). It is important to select manufacturers with proven expertise and solid quality standards, as the strap reflects the watch's value. Casati Milano offers bespoke service by appointment with full customisation options.

Durability depends on leather quality and frequency of use. A high-quality alligator or vegetable-tanned calfskin strap lasts 3–5 years with daily wear. Longevity extends significantly if the leather is protected from excessive water exposure and direct sunlight. With proper care (occasional application of vegetable balm, drying after moisture contact), an artisanal strap can exceed a decade of life. A cotton-and-silk NATO strap, if well-made, lasts 2–4 years before visible wear appears. Casati Milano guarantees 18 months against manufacturing defects.