Strap for Tri-Axial Tourbillon Titanium

The Girard-Perregaux Heritage 99815-21-653-BA6E is equipped with a 20mm lug width, the standard specification for this reference from the La Chaux-de-Fonds manufacture. Measurement is conducted using a digital calliper between the internal lugs of the titanium case, verifying that the selected strap adheres perfectly to the tapered geometry of the lugs themselves.

For this 46mm brushed titanium model, we recommend three complementary solutions: cognac alligator for formal contexts (enhances case sobriety), vegetable-tanned calf for those desiring patina development over time, and graphite-grey NATO for daily versatility. Selection depends upon your primary use context and propensity to embrace natural chromatic modifications in leather.

The procedure requires a spring bar tool (readily available from any watchmaker). Position the timepiece on a stable surface, gently insert the tool into the lateral aperture of the lug, lift the spring bar with measured pressure, remove the existing strap, and repeat for the opposite side. Insert the new strap ensuring the spring bar is perfectly seated. If uncertain, Casati Milano provides professional strap changes by appointment.

Certainly. The Girard-Perregaux Heritage 99815-21-653-BA6E accepts any strap with 20mm lug width, provided it is manufactured from quality materials (alligator, shell cordovan, vegetable-tanned calf, textile NATO, FKM rubber). Milano Straps offers artisanal straps specifically dimensioned for this specification, guaranteeing adhesion and geometric stability on the tapered lugs.

A quality leather strap (alligator, vegetable-tanned calf) maintains structural integrity for 5–8 years of daily wear, with variability based upon local climate and frequency of use. Natural leather is not a permanently stable material: fibre progressively stretches, and the buckle may wear. This process constitutes part of the aesthetic narrative of the artisanal strap. Entrust extraordinary maintenance (buckle retensioning, stitch reinforcement) to certified laboratories such as Casati Milano.