Strap for Datejust 31 White Gold Diamond / President / Silver

The lug width of the Rolex Datejust 31 178159-0018 is 16 millimetres. This measurement represents the distance between the two lugs on the case where the strap attaches. Accurate measurement with a ruler is essential to ensure compatibility with aftermarket straps. The 16mm specification is particular to this model and should not be confused with other Rolex references that may have different measurements.

For the Datejust 31 178159-0018 in white gold, alligator is the most refined choice, owing to its natural texture and ability to develop a beautiful patina over time. Vegetable-tanned calf leather offers excellent durability and chromatic versatility, maintaining everyday elegance. Shell cordovan is extraordinarily resistant and develops a natural polish. Your choice depends on usage: alligator for formal occasions, calf for daily wear, cordovan for those seeking longevity without aesthetic compromise.

Strap replacement requires specific tools: a spring bar tool. Position the watch on a stable surface, insert the flat tip of the spring bar tool into the small holes on either side of the upper lug, apply gentle outward pressure to release the internal spring, and slide out the old strap. Repeat with the lower lug. When fitting the new 16mm strap, align the holes with the lugs and press firmly until you hear a distinct click. If inexperienced, Casati Milano offers this service during an in-atelier consultation.

Any strap certified for 16mm lug width is compatible with the Datejust 31 178159-0018, including alligator, calf, shell cordovan, rubber, and fabric. Compatibility depends solely on lug width, not on the watch brand. Milano Straps provides a curated collection of 16mm straps crafted artisanally, available both online and bespoke at the Casati Milano atelier, ensuring quality and longevity superior to industrial alternatives.

A high-quality leather strap (alligator, vegetable-tanned calf, or shell cordovan) typically lasts 3–5 years with moderate daily wear. Longevity depends on frequency of wear, water exposure, climate, and maintenance. Prolonged tension, moisture, and intense perspiration reduce usable life. Straps made with vegetable tanning age more gracefully than chrome-tanned alternatives, developing character rather than degradation. Casati Milano's 18-month manufacturing guarantee covers structural defects, not natural wear.