Strap for Flagship 35.6 Automatic Stainless Steel Black

The lug width (ansa) of the Longines Flagship L4.774.4.52.6 is precisely 18.00 mm. This dimension is model-specific and requires straps constructed to this exact geometry for correct insertion into the case lugs. Measuring the distance between the two lateral pins on your watch case with a ruler allows you to verify this measurement directly.

Deep brown alligator (toasted or cognac tones) represents the historically correct and most elegant pairing for the Flagship in steel. The geometric texture of alligator creates harmonious visual contrast against the metallic rigour of the case. For those seeking chromatic evolution over time, vegetable-tanned calf leather is equally sophisticated; for summer wear, pure cotton NATO straps offer casual versatility without betraying the model's classical DNA.

Strap replacement requires a specialised tool: a spring bar remover. Position the watch on a stable surface, insert the flat tip of the remover under one lateral pin, lift gently to trigger the internal spring mechanism. Repeat for the opposite end. Insert the new strap by aligning the holes with the pins and pressing until they click into place. If you prefer professional assistance, an authorised retailer or Casati Milano atelier will execute the operation using proper tools.

Yes, provided the strap is constructed for 18 mm lug width. Many artisanal aftermarket straps fit perfectly and often offer construction quality superior to OEM straps. Always verify the strap is designated for 18 mm lug width and that material thickness aligns with case proportions (recommended thickness between 3.5 and 4 mm at lug-contact points).

Lifespan depends on material and usage intensity. A quality artisanal alligator strap ranges from 3 to 5 years in daily wear. Vegetable-tanned calf typically lasts 2 to 4 years relative to ambient humidity and wearing frequency. Cotton NATO straps can exceed 5 years. The critical factor is not chronological age but environmental exposure: sustained moisture, perspiration and friction accelerate deterioration. Applying vegetable-wax conditioner occasionally extends longevity. Casati Milano's standard warranty covers 18 months.