Strap for Constellation Co-Axial 35 Chronograph Double Eagle White Gold / Silver / Pink Alligator

The lug width of the Constellation 121.58.35.50.54.003 is exactly 18mm. This measurement is obtained by positioning a digital caliper between the inner edges of the case attachment holes. It is essential not to confuse this dimension with the strap thickness (3-5mm) or with the visual width on the case.

For the Constellation 121.58.35.50.54.003, fine-grained alligator and shell cordovan represent the most coherent choices with the delicate aesthetics of the case. Black alligator imparts formality, while deep burgundy shell cordovan develops a patina that accompanies the natural aging of white gold. For everyday versatility, a vegetable-tanned calf leather in cognac or medium brown tones offers balance between elegance and practicality.

The strap is attached to the case via two spring bars. To remove it, controlled pressure must be applied to the pins using a dedicated tool (spring bar tool) to make them snap out of their seats. The Constellation 121.58.35.50.54.003, with its 18mm lug width, requires particular attention to tolerances: the lugs of the new strap must have a thickness between 1.2 and 1.4mm to slide smoothly in the holes.

Yes. Milanostraps offers a collection of 18mm straps compatible with your Constellation, made in alligator, calf, shell cordovan, and rubber. All straps are available ready to ship, with customization options in sizes, initials, and choice of stitching thread. The Casati Milano atelier also creates bespoke straps with an 18-month warranty.

The lifespan of a leather strap depends on the quality of the material, the tanning method, and usage. Alligator and shell cordovan, if properly cared for (dried after humidity exposure), last 3-5 years of regular use. Calf leather with vegetable tanning has similar longevity. The standard warranty on artisan straps is typically 18 months from manufacture. Strap decline is gradual: it begins with loss of suppleness, continues with minor cracking on the edges, and ends when the lug begins to disintegrate.