Strap for Big Crown ProPilot Chronograph Stainless Steel / Grey / Bracelet

The lug width of this ProPilot is 22mm. This dimension is measured from the inner shoulder on the left to the inner shoulder on the right of the case—essentially the free space that will accommodate the strap ends. It is essential to verify this measurement before purchasing an aftermarket strap, as even half a millimetre difference will compromise the fit.

Given the avionic nature of this chronograph, three profiles are recommended: alligator in vegetable tanning (historical authenticity and patina), structured fine-grain calf leather (versatility and durability), and NATO in technical rubber or canvas (practicality in humid or flight environments). The premium eco-sustainable NATO represents the ideal compromise between formal aesthetics and operational functionality.

The strap is replaced via the lug pins (removable pin and washer, or screw, depending on the case attachment design). Position the watch with the lugs facing you, locate the access hole with a removable pin or thin screwdriver, and gently push the pin out of the case. Remove the old strap, insert the new one by aligning the ends to the lugs, and reinsert the pin. If unfamiliar with the procedure, consult a watchmaker; Milano Straps can recommend a certified technician.

Yes. Any commercial strap with a 22mm lug width is compatible, provided the ends are perfectly straight and the material is robust enough to withstand the anchoring force. Ensure the buckle (if present) is stainless steel and that any deployment clasp accommodates the rotational dynamics of the crown. Milano Straps offers a curated selection of 22mm straps tested on this category of watches.

Longevity depends on material, use, and climate. An alligator strap in vegetable tanning on a moderately worn aviator will last 3–5 years before partial replacement (strap end, buckle) becomes necessary. Calf leather ages more rapidly (2–3 years of daily wear) but patinas more predictably. Vulcanised rubber on a technical NATO will resist significant deformation for 4–6 years. In humid or airport-exposed climates, durability decreases by 20–30%.