Rolex
Day-Date 36 118239-0280— lug 20mm

The Rolex Day-Date 36 118239-0280 features a lug width of precisely 20 millimetres, measured from the innermost point between the lugs to the opposite extremity. This width is specific to the Day-Date President 36mm family and is not interchangeable with alternative sizes such as 19mm (Datejust) or 21mm (oversized models). To verify compatibility, use a digital calliper, inserting the tip perpendicularly between the lugs of the case.

Alligator remains the primary aesthetic choice for the 118239-0280: the natural texture of the reptile skin dialogues perfectly with the geometric rigidity of white gold. Effective alternatives include vegetable-tanned calf leather (which develops patina over time), structured rubber for summer contexts, and in rare instances, silk fabrics. Material selection depends on the desired chromatic balance: brown alligator emphasises warm-cold tones, black radicalises formal contrast, dark blue introduces discreet sophistication.

The Day-Date 36 typically utilises quick-release spring bars (push-fit mechanism). Position the watch with the wrist facing downwards, insert a flat tool (spoon-style strap tool) into the small hole on the inner side of the lug, gently press the spring towards the case and withdraw the lug from the pin. Repeat for the opposite lug. When reinstalling the new 20mm strap, ensure the pins are fully inserted into the holes before releasing the spring. A specialist atelier guarantees this operation without risk of micro-scratching the case.

Yes, provided the lug width is precisely 20 millimetres. Many international artisanal manufacturers produce compatible straps for the President 36mm, but it is essential to verify tolerances: a variation of only 0.5mm can cause harmful lateral oscillation over time. Casati Milano and other specialist ateliers cut straps to measure for this reference, guaranteeing millimetre accuracy. Avoid generic manufacturers that simply declare "20mm" without specific fit verification.

A leather strap in artisanal alligator or calf, subject to moderate daily use, maintains structural integrity for 4 to 7 years before requiring the first restoration. Natural leather ages, accumulating patina, microscopic creases and variations in thickness. Factors that accelerate wear: constant moisture (perspiration, humid environments), repeated mechanical bending, direct heat exposure. A well-maintained strap—regularly dried, alternated with other models—can exceed a decade of service. Casati Milano offers repairs and restorations to extend strap life beyond the initial 18-month guarantee.