Strap for Big Crown Royal Flying Doctor Service II Stainless Steel / Black

The lug width of this model is 22mm. Measurement is taken from the inner aspect of the lugs, side to side across the case. This is the standard lug width for Big Crown watches of this generation and accommodates robust straps without visual disproportion relative to the 45mm case diameter.

The superior aesthetic and functional pairing is an alligator strap with vegetable tanning, in cognac or honey tones: the natural texture of crocodile harmonises with the patina of the steel case and reflects the aviatory heritage of the Big Crown. For informal contexts, a dark brown vegetable-tanned calf leather is equally elegant. If destined for marine or sporting use, a cotton NATO or FKM rubber are pragmatic and authentic choices.

The Oris Big Crown employs fixed lugs (not spring bars): a spring bar remover tool is required to disengage the lateral lugs from the case. Insert the tool into the lug seat, apply gentle pressure to release the internal spring, and the old strap slides free. Verify that the new strap has precisely 22mm lugs to ensure secure fitment. If you lack the necessary tools, consult a certified watchmaker.

Yes, absolutely. Any strap with a 22mm lug width is compatible with the Big Crown 01 735 7728 4084-Set LS Kroko. Milano Straps offers a comprehensive collection of artisanal straps in alligator, calf, NATO, and rubber, all calibrated for this specification and ready for dispatch. The construction quality of an artisanal strap often surpasses that of the OEM strap.

A high-quality vegetable-tanned leather strap (alligator or calf) typically lasts 3–5 years with daily wear, provided basic maintenance: avoid prolonged water immersion, dry after perspiration, and occasionally apply a neutral balm to maintain elasticity. Alligator ages superior to calf, developing a patina that increases aesthetic value. An FKM rubber or NATO strap lasts 4–7 years and requires only periodic cleaning with tepid water.