IWC
Pilot IW3713-18— lug 21mm

The IWC Pilot IW3713-18 has a lug width of 21mm. This dimension represents the internal distance between the lugs on the case where the strap attachments are anchored. Always verify this measurement before ordering an aftermarket strap, measuring it directly on the case.

For this professional chronograph, straps in alligator (developing natural patina over time), satin European calf leather for formal sobriety, or NATO in cotton/Cordura to maintain the military-aviation heritage are ideal. Synthetic rubber is the modern choice for humid environments. Avoid thin straps: robustness is essential for this 42mm case.

Position the watch on a soft surface (cloth or cushion). Locate the lugs (the metal cylinders on the sides of the case). Use a spring bar tool or small flat screwdriver to gently push the retaining pin downward, sliding the old strap out. Align the lugs of the new strap and reinsert the pin until you feel a click lock. Some IWC authorized dealers offer this service free of charge.

Yes, provided the lug width is exactly 21mm. Many quality aftermarket straps (especially handcrafted ones such as those from Milano Straps) are made to measure and offer guaranteed compatibility. Always verify the lug width declared by the manufacturer and specifically request compatibility with the IW3713-18 model.

A quality handcrafted alligator or calf strap, with regular maintenance (protection from stagnant water and periodic cleaning), lasts an average of 5-7 years of intensive use. Leather tends to wear primarily at flex points (keeper and buckle area). Straps subjected to vegetable tanning develop an attractive patina over time, aging with dignity. Casati Milano offers an 18-month warranty on custom straps.