Strap for Pilot's Watch Spitfire Chronograph Stainless Steel / Black / English / Strap

The lug width of the IWC Pilot IW3706-13 is 20 mm. This measurement represents the internal space between the spring bars that connect the case to the strap. Accurate measurement is essential before purchasing an aftermarket strap, as an incorrect width would result in incompatibility and compromised aesthetic fit.

The ideal strap depends on intended use. For formal elegance, we recommend dark brown alligator or black vegetable-tanned leather. For a more casual and tactical aesthetic, a grey NATO strap or grey FKM rubber strap maintains the aeronautical authenticity of the model. Medium brown alligator represents the ideal aesthetic compromise between sophistication and functionality.

Strap replacement requires a spring bar tool (extractor). Position the tool beneath the spring bar and apply gentle upward pressure to release the spring mechanism. Once the bar is extracted, remove the original strap and insert the new one, ensuring the spring bar clicks firmly into both lugs of the case. If you lack experience, consult a professional horologist.

Yes, any strap with a 20 mm lug width is mechanically compatible with your IW3706-13. However, to ensure construction quality and long-term durability, we recommend luxury leather straps (alligator, vegetable-tanned leather, shell cordovan) crafted by specialised artisans. MilanoStraps offers a curated selection of 20mm straps tested for compatibility and reliability.

Lifespan depends on material and usage. A high-quality vegetable-tanned leather strap resists 3–5 years of daily wear, developing natural patina over time. Alligator, more durable, can last 5–7 years. FKM rubber offers similar longevity but requires less frequent maintenance. Proper care—drying after moisture exposure and periodic conditioning—significantly extends strap life.