Strap for Pilot's Watch Spitfire Double Chronograph Stainless Steel / Black / Italian / Bracelet

The IWC Pilot IW3713-37 features a lug width of 21mm. This measurement is the distance between the lugs on the case, and any compatible aftermarket strap must conform to this specification. Accurate measurement of the space between the lugs is essential before ordering a replacement strap.

A dark alligator strap with vegetable tanning, or shell cordovan, are excellent choices for the IW3713-37. Medium-grain alligator leather imparts sophistication without contradicting the instrument-focused aesthetic of the case; shell cordovan develops a natural burgundy patina over time. Alternatively, a reinforced NATO fabric strap reinforces the model's technical vocation.

Strap replacement on the IW3713-37 is accomplished by manipulating the spring bars located at the lug ends. A dedicated spring bar tool compresses the bars, allowing them to disengage from their seats. Work on a stable surface with adequate lighting. If you are unfamiliar with the procedure, Casati Milano atelier performs the service by appointment with full assurance.

Yes, provided the strap is compatible with the 21mm lug width specification. Artisanal aftermarket straps offer greater aesthetic and construction freedom than original IWC straps. Online retailers stock extensive selections of 21mm-compatible straps in various materials, finishes, and colour options, customisable to specification.

Leather strap longevity depends on usage intensity, construction quality, and tanning method. An alligator strap with vegetable tanning typically lasts 5–8 years with daily wear; shell cordovan may last up to 10 years. Quality leather straps require periodic care—brushing, water and moisture protection—to preserve their structural integrity over time.