Strap for BC4 Flight Timer Stainless Steel / Black

The Oris BC4 01 690 7615 4164-07 5 22 58FC features a lug width of 22 millimetres, measured centre-to-centre at the lugs. This dimension is typical of Swiss tool watches and aviators, ensuring harmonic proportions on a case diameter of 42.7 millimetres. It is essential to verify this measurement before ordering an aftermarket strap to avoid mechanical play or construction incompatibility.

For the BC4 01 690 7615 4164-07 5 22 58FC, straps in calf leather, shell cordovan, NATO in technical fabrics, and vulcanised rubber are suitable. Selection depends on intended use: vegetable-tanned calf offers natural patina and elegance without compromising practicality; navy or black NATO emphasises aviator and instrumental vocation; rubber is ideal for water sports and extreme conditions. Milano Straps offers 22mm straps in all these categories, customisable and ready for shipment.

Strap change on the BC4 01 690 7615 4164-07 5 22 58FC is performed by removing the spring bars that connect the strap to the lugs. Using a dedicated tool (spring bar tool), press the bar from the lower side to release the old strap, then insert the new strap (compatible with 22mm lug width) into the grooves of the lugs. The operation is reversible and requires no specialist technical knowledge; however, the Casati Milano atelier can provide strap replacement with guidance on aesthetic matching and material selection.

Any strap with a 22 millimetre lug width is compatible with the BC4 01 690 7615 4164-07 5 22 58FC. This includes leather straps (calf, shell cordovan, alligator), NATO, technical fabrics, rubber, and steel. However, it is advisable to select straps of construction quality equivalent to the watch itself: manufacturers such as Milano Straps specialise in artisanal production with leather of controlled origin and deployante or buckle finishes, guaranteeing mechanical compatibility and durability over time.

The lifespan of a leather strap depends on the material, tanning method, and intensity of use. A calf strap with vegetable tanning, if worn daily and subjected to periodic maintenance (drying after moisture, light cleaning), maintains structural functionality for 3–5 years; subsequently, the leather naturally thins and requires replacement. Shell cordovan, thanks to its superior density, can last 5–7 years or longer. NATO straps in regenerated fabrics have similar longevity (3–4 years in intensive use), whilst vulcanised rubber degrades after 4–5 years due to UV exposure and extreme temperatures. Strap replacement on the BC4 01 690 7615 4164-07 5 22 58FC is straightforward and recommended every 3–5 years to maintain overall timepiece reliability.