Strap for Flagship 40 Stainless Steel / Blue / Bracelet

The lug width of the Longines Flagship L4.984.4.92.6 is 21mm. This measurement refers to the inner space between the two horizontal lugs where the strap sits. It is a specific dimension for this model, different from standard 20mm or 22mm sizes, so selecting a strap precisely dimensioned at 21mm is essential for a perfect fit.

The ideal strap depends on your daily usage. For formal contexts, we recommend alligator in dark shades (brown or black) or vegetable-tanned calf leather, which will develop natural patina over time. For a balance between elegance and practicality, shell cordovan offers exceptional durability and natural lustre. NATO fabric or vulcanised rubber straps represent modern options for those prioritising functionality. All materials must be rigorously 21mm in width.

Changing the strap requires a specific tool (spring bar tool) and gentle pressure to compress the horizontal spring pins. The procedure involves carefully lifting the old strap, extracting the pin, inserting the new strap, and repositioning the pin within the new lug. If you feel uncertain, consult a qualified artisan. Atelier Casati Milano offers fitting service by appointment.

Yes, absolutely. Any quality strap with a 21mm lug width is compatible with the Longines Flagship L4.984.4.92.6. Online you will find a wide selection of 21mm straps ready for shipment and customisable in material, colour and finishes. The important thing is to verify that the width is precisely 21mm to ensure a flawless fit without lateral play.

The lifespan of a leather strap depends on the material, tanning method and intensity of use. A quality artisanal alligator strap with vegetable tanning can last 5–10 years with proper maintenance (drying after moisture exposure, periodic cleaning). Calf leather tends to wear more quickly (3–5 years), while shell cordovan offers greater longevity (7–12 years). Ordinary leather straps require replacement every 1–3 years. Casati Milano's 18-month guarantee covers manufacturing defects.