Strap for Big Crown ProPilot Big Date Stainless Steel / Blue / Fabric

The Oris ProPilot 01 751 7761 4065-07 3 20 05LC features a lug width of 20 millimetres. This specification defines the distance between the two lugs—the metal projections on the case—where the strap passants attach. Verification of this measurement is critical before ordering a replacement strap: 18mm or 22mm dimensions would not fit correctly.

The optimal strap choice depends on intended use. For formal and professional contexts, we recommend alligator leather in dark brown or saturated black, which amplifies the instrumental character and develops patina over time. For humid climates or recreational aquatic activities, select heavyweight nylon NATO fabric or satinous synthetic rubber. Vegetable-tanned calf leather represents the ideal compromise between artisanal authenticity and daily versatility.

To change the strap: (1) Ensure the threaded crown is fully screwed down; (2) Insert the pointed end of a spring bar tool into the small opening beneath the case lug; (3) Lift gently to disengage the lug spring—the old strap will detach; (4) Insert the tool's pointed end through the new strap hole, align with the lug and press until a tactile click occurs. Repeat on the opposite lug. The tolerance is tight (exactly 20mm): avoid forcing.

Yes, absolutely. Quality 20mm aftermarket straps are fully compatible with the ProPilot. Milanostraps.it supplies artisanal straps in leather, NATO and rubber, all tested for dimensional tolerance and lug-bending compliance. A quality aftermarket strap will perform as durably as the original Oris strap, with the advantage of superior aesthetic and tactile customisation.

A quality vegetable-tanned leather strap lasts 3–5 years with daily wear, depending on change frequency, moisture and heat exposure. Leather gradually thins at flex points (passants)—a natural process. To extend durability: (1) Alternate straps—avoid continuous use of one strap; (2) Condition with neutral wax every 6–8 months; (3) Dry completely after rain exposure; (4) Protect from prolonged direct sunlight. Shell cordovan offers 30% superior durability, though initial cost is higher.