Strap for De Ville Co-Axial 42 Chronograph Stainless Steel / Black

The lug width is 20mm. This measurement is specific to the 431.13.42.51.01.001 model and should not be confused with other sizes: a strap of 20.5mm or 21mm could rub against the case. Measure the inside of the lugs (the pins on which the strap is attached) to verify exactly 20.00mm.

Vegetable-tanned alligator is the ideal choice to preserve the urban and classical aesthetic of the De Ville: the natural texture and the patina it develops over time align with the sobriety of the case. Box calf and shell cordovan are sophisticated alternatives; woven NATO is suitable for informal sporting contexts.

Use a spring bar tool by inserting the tip into the small groove next to each lug. Press gently downward to release the tension spring, then pull out the spring bar. Repeat on the other side. To fit the new strap, align the bars with the grooves and press until the spring snaps into place.

Only straps with a 20mm lug width are compatible with the 431.13.42.51.01.001. Smaller widths (18mm) or larger ones (22mm) create mechanical play or friction against the case. Always verify the lug width before purchase to avoid incompatibility.

With vegetable tanning and moderate daily use, an artisanal 20mm strap lasts on average 2-3 years before requiring replacement. Aging accelerates with exposure to sweat, humidity and sunlight. The Casati Milano warranty is 18 months; after this period the leather can be re-dyed or replaced.