Strap for Flagship 38.5 Black / Bracelet

The Longines Flagship L4.874.4.52.6 features a lug width of 20 mm. This measurement is precise and non-negotiable: it was designed to maintain balanced proportions of the 38.50 mm case. To verify, measure the internal spacing between lugs with a digital calliper, positioned approximately 1 mm from the lug shoulders.

Alligator is the formal choice: its fine grain accentuates the case's pure lines without distraction. Select dark tones such as cognac, chocolate brown, or black. Vegetable-tanned calf leather is a conventional alternative with pronounced texture and evolving patina. For refined elegance, burgundy shell cordovan offers exceptional waxy texture.

Obtain a spring bar removal tool. Place the watch on a soft surface with the case facing upward. Insert the tool into the small groove of the lug, pushing downward to release the spring. Withdraw the steel lug, then repeat on the opposite side. Insert the new strap's lugs by reversing the procedure: align the holes, push until the retention click.

Yes, provided it strictly respects the 20 mm width. A wider strap (22–24 mm) creates visual imbalance; a narrower one (18 mm) appears fragile. Select suppliers using vegetable-tanned leather and stainless steel or gold-plated buckles. Deployante clasps are preferable to pin buckles as they reduce wear.

A quality calf or alligator strap, vegetable-tanned, typically lasts 2–4 years under daily wear and moderate moisture exposure. Ageing is natural and desirable: patina develops progressively. Shell cordovan, being denser, may last 4–6 years. Maintenance includes periodic cleaning with a damp cloth and annual hydration with specific balms. Avoid prolonged water immersion.