Strap for Seamaster Diver 300M Co-Axial 41 Stainless Steel / Blue / Rubber

The lug width is exactly 20mm. It is measured from the inner diameter of the metal guide that houses the spring bar, shoulder to shoulder of the lug. This standard measurement guarantees full compatibility with our artisanal straps, with no need for adapters or modifications.

For this reference we recommend: alligator (fine grain, sporty elegance), Shell Cordovan for those who appreciate patina evolution over time, natural vulcanized rubber for intense aquatic use, or vegetable-tanned calf for tactile sobriety. The choice depends on the dial: blue wave prefers black alligator, while black dials benefit from dark brown Shell Cordovan.

Proceed with a standard spring bar (available in watch disassembly kits) by inserting the tip into the side slot of the lug. Gently remove the spring bar, extract the pin, then lift off the old strap. Position the new 20mm strap, reinsert the pin and spring bar until the locking click. If you lack experience, rely on Casati Milano to perform the operation without risk.

No, absolutely not. The 2920.80.91 features a 20mm lug width, standard for sporty Seamaster models from the 2000-2010 era. More recent models (42mm Sport) feature 22mm, while dress versions feature 18mm. Always verify the lug width before purchase. Our 20mm straps are specific to this reference and contemporary models with identical geometry.

With moderate use (absence of frequent immersions), an alligator or vegetable-tanned calf strap lasts 4-6 years before replacement is needed. Vulcanized rubber resists 3-4 years if exposed to chlorine or salt frequently. Shell Cordovan evolves aesthetically indefinitely but the leather backing lasts 5-7 years. Casati Milano warranty is 18 months on all artisanal straps.