Strap for Heritage Chronometrie Perpetual Calendar Stainless Steel / Sapphire

The lug width of the Montblanc Heritage 118513 is precisely 20mm, measured between the centres of the lugs that connect the case to the strap. This dimension represents the European standard for watches ranging from 38–42mm in diameter, ensuring visually balanced proportions on an average wrist.

We recommend a vegetable-tanned leather strap in cognac brown or black for the 118513. Alligator leather represents the premium option for guaranteed durability. For daily wear, cotton NATO or FKM rubber straps offer practicality without compromising elegance. Your choice depends on usage: formal contexts favour leather; sportive-casual contexts suggest NATO or rubber alternatives.

Strap replacement requires a spring bar tool. Position the tool on the spring bar beneath the lug, pressing gently upward until it releases. Extract the bar and repeat on the opposite side. Align the new strap's holes with the case lugs and reinsert the spring bars until you hear a click. Verify the strap is centred and does not rotate around the pins.

Any strap with a 20mm lug width is compatible. Milano Straps offers a curated selection of artisan straps in vegetable-tanned leather, alligator, NATO, and rubber, all engineered for this standard width. Custom straps can be ordered online; verify the pin diameter (typically 1.6mm) to ensure a perfect fit.

A vegetable-tanned leather strap used daily maintains optimal functionality for 3–5 years before replacement becomes necessary. Longevity depends on ambient humidity, frequency of use, and maintenance habits. An alligator strap can last 7–10 years. Applying a vegetable-based conditioner periodically extends its lifespan. Gradual wear (creases, subtle creasing) constitutes natural patina, not a defect.