Strap for Master Collection 40 Chronograph Calendar Yellow Gold / Silver / Bracelet

The lug width of the Longines Master Collection L2.673.6.78.6 is 21 millimetres. This measurement, taken from the outer face of one lug to the other, determines compatibility with aftermarket straps. For precise verification, use a digital calliper positioned perpendicularly between the two lateral pins of the case.

For this 40mm yellow gold model, alligator leather represents the stylistically most coherent choice: the natural texture dialogue with the Clous de Paris dial. Alternatively, vegetable-tanned calf leather offers a more pronounced grain and a rigidity that naturally softens with use. Avoid rubber or synthetic combinations, which would create discord with the case's precious material.

The change is accomplished by extracting the lateral pins (spring bars) that connect the case to the strap. Position the watch on a flat surface, use a spring bar tool (a specific implement equipped with a fork and lever) to gently lift the pin on one side, then remove the old strap. Insert the new strap by aligning the lugs to the case seats, then press the pin until you hear the safety click. Avoid excessive force to prevent damage to the seats.

Yes, the L2.673.6.78.6 model accepts all straps with a 21mm lug width compatible with your wrist and aesthetic preferences. Milanostraps provides a collection of 21mm straps customisable in leather (alligator, calf, shell cordovan), size, stitching thread and initials. Always verify that the chosen strap has a slightly curved lug: this characteristic ensures perfect grip on the case.

The lifespan of a leather strap varies depending on the material, usage and maintenance. An alligator strap with vegetable tanning can last 4–6 years of daily use before requiring replacement, thanks to the natural resilience of the leather. Shell cordovan, more robust, can exceed 5–7 years. To extend life, protect the strap from prolonged sun exposure, avoid immersion in fresh water (your yellow gold Longines has water resistance limited to 30 metres) and occasionally rotate between two straps to allow the leather to 'breathe'. Casati Milano provides an 18-month warranty on every bespoke strap.