Strap for Day-Date 36 White Gold Diamonds / President / MOP

The lug width of the Day-Date 36 reference 118389-0012 is exactly 20 millimetres. This measurement is specific to the 36-millimetre model and is critical for ensuring compatibility with aftermarket straps. To verify it, position a ruler across the lugs and measure the internal distance with precision. A measurement error can compromise the watch's usability.

For the Day-Date 36 in white gold, alligator represents the classic choice: its geometric grain and natural suppleness maintain the formal rigour typical of a dress watch. Alternatively, vegetable-tanned calf offers a patina that improves with age; shell cordovan provides initial stiffness that becomes organic flexibility; rubber is ideal for more casual wear. Recommended colours are chocolate brown, polished black, or deep burgundy.

To change the strap, remove the spring bar — the metal pin connecting the strap to the two case lugs. Use a dedicated spring bar tool to gently push the small lateral clasp, creating the necessary space to extract the pin. Insert the new strap ensuring the spring bar is positioned symmetrically and that the lateral clasps lock completely. If inexperienced, consult a qualified watchmaker.

Yes, any strap manufactured for a 20-millimetre lug width is compatible with the Day-Date 36. It is essential to verify this measurement before purchase. Choosing an aftermarket strap allows you to personalise the watch with superior materials — such as alligator, shell cordovan, or vegetable-tanned calf — whilst maintaining full technical and aesthetic compatibility.

The lifespan of a leather strap depends on the intensity of daily wear and the quality of the tanning. A high-quality artisanal alligator or shell cordovan strap lasts an average of 3–4 years of regular use, developing a natural patina that increases its appeal. Calf leather may last 2–3 years. Exposing the strap to moisture, excessive perspiration, or direct sunlight reduces longevity. Proper maintenance — gentle cleaning and storage in dry environments — significantly extends the product's lifespan.