Strap for La Grande Classique Tonneau 30 Stainless Steel

The lug width of the Longines La Grande Classique L4.705.4.58.2 is 18 mm. This measurement is specific to the case geometry and is not a generalised standard. The measurement must be taken between the two lugs, excluding the pins themselves. A 16 mm strap would appear undersized, while a 20 mm strap would overburden the minimalist proportions of the watch.

The most appropriate material is alligator in vegetable tanning, which preserves the aesthetic sobriety of the watch through its linear grain and fine texture. Equally excellent are calf leather, shell cordovan, and, for less formal use, sculptural rubber. The choice depends on the context of use and personal preference for chromatic warmth. All these materials are available from Casati Milano in bespoke versions tailored to this specific lug width.

Strap replacement requires a specific spring bar tool to extract the lug pins. Position the watch on a stable support, locate the two lateral pins and use a spring bar tool to remove them gently. Once the old strap is removed, insert the new strap into the case, ensuring the pins are correctly aligned, then reinsert the pins. If you lack experience, it is advisable to consult a professional or contact Casati Milano for assistance.

Yes, numerous aftermarket straps compatible with 18 mm lug width are available. Milano Straps offers a dedicated collection of ready-to-ship straps, customisable in size, initials and stitching thread choice. For an even more refined and personalised experience, Casati Milano's atelier produces bespoke straps with direct leather selection and exclusive construction details, guaranteed for 18 months.

The lifespan of a leather strap depends on the material and usage conditions. A vegetable-tanned alligator or calf strap, used with moderate care and protected from excessive humidity, typically lasts 3-5 years before requiring replacement. Shell cordovan, if maintained regularly, can exceed 5-7 years. The patina developed over time represents a sign of nobility, not degradation. Casati Milano's atelier offers an 18-month warranty on all handcrafted straps and recommends periodic maintenance with products specifically formulated for fine leathers.