Rolex
Day-Date 36 118139-0090— lug 20mm

The lug width of the Rolex Day-Date 36 reference 118139-0090 is precisely 20mm. This dimension is exact and non-negotiable: any compatible strap must measure 20mm internally from one lug to the other to ensure perfect fit through the watch's attachment pins.

Alligator leather with vegetable tanning is the most elegant choice for the white gold Day-Date 36: its fine grain and natural patina dialogue beautifully with the metal's luminosity without competing. Box calf is a contemplative alternative that develops an increasingly noble patina over time. Shell cordovan, if available in 20mm, offers superior natural sheen with exceptional durability.

Changing the strap on the Day-Date 36 requires precision spring bars and a dedicated pin removal tool to extract the attachment pins from the lugs. It is recommended to entrust this to an authorised watchmaker or specialised artisan: the risk of scratching white gold is considerable for those without the specific tool and experience. Casati Milano offers assistance on existing watches.

Yes, if constructed with a 20mm lug width. Artisanal quality leather straps guarantee perfect compatibility with original Rolex pins. It is essential to verify that the width is exact: even a minor discrepancy compromises both aesthetics and functionality. Milanostraps offers a dedicated collection of 20mm-compatible straps.

A high-quality artisanal alligator or calf strap typically lasts 3–5 years with daily wear, depending on tanning method and climate. The leather develops a natural patina and darkens, adding character. Shell cordovan is more resistant and may last 5–7 years. Longevity depends on maintenance: avoid excessive moisture and clean with a soft, dry cloth.