Strap for Motorsport Automatic Chronograph PVD / Carbon Bezel / Black / Limited Edition / Calf

The lug width of the Formex Motorsport 3100.9.8299.216 is 25mm. This is a non-standard measurement that characterises professional-grade sports chronographs. The measurement is taken by measuring the internal distance between the two lugs where the strap attaches to the case.

The best strap depends on your intended use. For daily sports wear, we recommend vegetable-tanned calf leather with pronounced grain, which ages naturally over time. For maximum practicality, a black vulcanised rubber strap maintains authentic motorsport aesthetics. For formal contexts, marbled alligator or grey creates elegant contrast against the titanium-carbon case.

Changing the strap requires a spring bar tool (a two-pronged instrument). Insert one prong into the small hole beneath the lug and gently compress the elastic pin; withdraw the strap. Align the new strap and re-insert the pin into the corresponding hole. If you lack the tool, seek assistance from a local watchmaker or contact our Casati Milano atelier for bespoke customisation services.

Yes, all 25mm straps are compatible with your watch. We offer a comprehensive collection of handcrafted straps in leather (alligator, calf, shell cordovan), NATO fabric and rubber, specifically engineered for this lug width. Each strap is customisable to your specifications at the Casati Milano atelier.

Durability depends on material and usage intensity. Quality vegetable-tanned calf lasts 3-5 years under intensive daily wear before replacement (though the material develops a prized patina during this period). Premium alligator or shell cordovan may last 5-8 years. Vulcanised rubber straps maintain structural integrity for 5-7 years before micro-fractures appear. Early replacement is advised if the material loses elasticity.