Strap for Fifty Fathoms Bathyscaphe Ceramic / Blue / NATO

The lug width of this model is 23mm. This measurement represents the internal distance between the two lugs (metal bars) that pass through the case laterally. To measure accurately, use a digital calliper positioned perpendicularly between the lugs themselves. Do not measure from the outer tip of the spring bars: this is a common error that leads to oversized straps.

Top-grade alligator is the traditional aesthetic choice: controlled grain, noble patina, excellent durability. For authentic marine use, FKM rubber with titanium deployante is superior: waterproof, thermoelastic, entirely functional. NATO-style nylon Cordura straps offer tactical lightness and rapid drying. Your choice depends on intended usage and your personal balance between aesthetics and performance.

Obtain a spring bar tool (fork-shaped implement specific to watchmaking). Position the tool in the lateral groove of one lug spring, press gently towards the case centre to release tension, then extract the pin. Repeat on the opposite side. Insert the new strap by aligning the holes to the lugs, then reinsert the pins using the same tool to compress the lateral springs. Avoid damaging the pins or lugs: they are essential components of the diving seal.

Yes. Any strap with 23mm lug width is mechanically compatible. Milano Straps offers a dedicated collection of artisanal 23mm straps, crafted with selected raw materials (alligator, shell cordovan, European calf, FKM rubber). All straps are tested for resistance and compatibility with Blancpain lugs. We recommend visiting the 23mm collection and selecting based on your intended use: frequent diving (rubber), formal wear (alligator), daily compromise (calf).

Durability depends on material and exposure. Top-grade alligator resists 3–5 years with regular use and minimal care (drying after bathing, avoiding prolonged immersion with leather strap). European calf is estimated at 2–3 years. FKM rubber lasts 5–7 years in intense marine use. Constant exposure to saltwater, chlorine, and UV rays accelerates ageing in any leather. With Casati Milano, you receive an 18-month warranty on manufacturing defects, but longevity also depends on the user's maintenance choices.