Strap for Portofino Automatic Stainless Steel / Black - Pilot / Strap

The lug width of the IWC Portofino IW3513-22 is precisely 18 millimetres. This dimension represents the constructive balance between the compact 34mm case diameter and the structural requirements of the strap. To measure correctly, use a digital calliper positioned perpendicularly across the midpoint of the lugs: the result should be 18mm with IWC construction tolerances typically within ±0.2mm.

For the Portofino IW3513-22, we recommend alligator leather or vegetable-tanned calf: both dialogue aesthetically and technically with the brushed stainless steel case. Alligator offers regular grain and a patina that nobly ages; vegetable-tanned calf's structured texture contrasts elegantly with the white dial. A ballistic canvas NATO in charcoal grey is also compatible for those seeking casual versatility. Avoid synthetic leather or low-quality rubber straps that do not respect the case's engineering.

Strap removal on the IW3513-22 requires a dedicated spring bar tool sized for 18mm lugs. Position the watch with the strap facing upward, insert the tool into the lug slot, gently press downward to release the spring tension, then extract the stainless steel pin. Repeat on the other side. For installation of a new strap, align the pins and press with the tool until the spring engages. If uncertain, the Casati Milano atelier executes the change with technical precision and without risk to the case.

Yes. Any strap with an 18-millimetre lug width is compatible with the IW3513-22, provided it respects the internal width standard. High-quality artisanal aftermarket straps, such as those in alligator or calf with hand-stitching, often offer aesthetic superiority to original IWC straps by allowing choice of materials, finishes and customisations. Always verify that the lug width is exactly 18mm and that the spring bars are adapted to the lug geometry.

A high-quality natural leather strap (alligator, vegetable-tanned calf, cordovan) typically lasts 3–5 years of daily wear before requiring replacement, depending on humidity exposure, direct sunlight and frequency of use. Vegetable tanning degrades slightly faster than chrome tanning, but develops a patina appreciated by collectors. Synthetic leather straps last 1–2 years. Extend strap life by protecting it from nighttime humidity, cleaning monthly with microfibre cloth and occasionally applying a natural leather conditioner. The Casati Milano atelier offers an 18-month warranty on all custom-made straps.