Strap for De Ville Trésor Master Co-Axial Stainless Steel / Diamond / Orbis

The lug width of the Trésor 432.18.40.21.03.001 is 20mm. This is a standard measurement for 40mm watches of this caliber, but it is essential to verify it with a digital caliper before purchasing an aftermarket strap to avoid visual misalignment and mechanical stress on the lugs.

The choice depends on usage: for formal elegance we recommend American alligator with regular grain; for everyday versatility, vegetable-tanned calf leather in brown or black tones; for authentic sportiness, NATO in grey or navy blue technical fabric. The brushed steel case tolerates all these materials without aesthetic conflicts.

The Trésor uses standard spring bar or bayonet lugs. Insert the spring bar tool under the lug from the inside of the case, press upward to release the spring, remove the old strap, and reinsert the new one by aligning the lug holes with the spring pin. For precision work, the Casati Milano atelier offers professional strap change service with guaranteed tolerances.

Yes, all straps with 20mm lug width are compatible. Online at milanostraps.it you will find a complete selection of 20mm straps ready for shipment in different materials, or you can order a custom strap from Casati Milano with choice of leathers and finishes.

A quality leather strap (alligator or vegetable-tanned calf) lasts 3-5 years with moderate daily use. Aging accelerates if exposed to frequent moisture or perspiration. Vegetable-tanned calf with vegetable tanning develops a desirable patina over time; alligator maintains its shape longer. Casati Milano's 18-month warranty covers manufacturing defects and allows for scheduled maintenance.