Patek Philippe
Calatrava 3718A Slate— lug 18mm

The lug width of the Patek Philippe Calatrava ref. 3718A Slate is 18mm. This dimension represents the distance between the two case lugs that support the strap. It is essential to measure this distance accurately before purchasing an aftermarket strap, using a calliper and positioning it perpendicular to the case plane.

For the Calatrava 3718A Slate, straps in grey or black alligator, vegetable-tanned calf leather, or high-quality rubber are recommended. Alligator represents the most traditional and authoritative choice, particularly in smoke grey tones that create chromatic continuity with the slate dial. Vegetable-tanned calf offers greater daily versatility with a patina that evolves over time. Rubber is ideal for those using the watch in more informal contexts.

Strap replacement requires the use of a spring bar tool or stainless steel pin of appropriate diameter (typically 1.5-1.8mm). Gently remove the pin from the case, extract the original strap and insert the new strap in the same direction, ensuring that the pin is fully inserted and that the strap moves smoothly. For models with integrated bracelets such as the 3718A Slate, it is advisable to entrust the work to a specialised craftsman to maintain case integrity.

Yes, any strap with an 18mm lug width is compatible with the Calatrava 3718A Slate. It is critical to verify that the lug width is actually 18mm before purchase. High-quality artisanal straps, made with fine leather and stainless steel or gold fittings, guarantee durability and aesthetics consistent with the prestige of the Patek Philippe piece.

The lifespan of a leather strap for the Calatrava 3718A Slate depends on the material, frequency of use and care. A high-quality artisanal alligator or calf, used with moderate frequency (2-3 times per week), can last 2-4 years before requiring replacement. Intensive daily use can reduce lifespan to 12-18 months. High-density rubber offers greater durability, up to 3-5 years. Proper drying after humidity exposure significantly extends strap service life.