Strap for Portugieser Perpetual Calendar 5023 Platinum / Silver

The IWC Portugieser IW5023-05 features a lug width of 22mm. This measurement represents the distance between the inner teeth of the spring bars on the case. To verify strap compatibility, measure with millimetre precision at the narrowest point where the strap's end inserts between the lugs: no approximation is acceptable with this platinum reference.

Genuine alligator remains the preferred choice: its natural grain offers an exceptionally fine granular texture that dialogues perfectly with platinum's cool character. Alternatively, shell cordovan in burgundy or dark brown creates a rich assonance, developing a noble patina over time. Vegetable-tanned calf represents the balanced option, ensuring predictable ageing and colour stability.

The Portugieser utilises spring bars that require delicate handling. Position the watch with the case facing upwards; using a spring bar tool, gently compress the spring bar on one side, creating space to extract the previous strap's end. Insert the new strap by aligning its hole with the lug, then compress and allow the spring bar to resume its original position. Avoid forcing: movement must be fluid and precise.

No, if the measurement is correct. A 22mm strap manufactured to IWC specification inserts into the lugs without dangerous friction or play. However, 21.5mm or 22.5mm straps can cause accelerated wear to the case's internal lug shoulders and stress the spring bars. Always verify compatibility with a millimetre ruler before purchasing. Milano Straps' artisanal straps are crafted to IWC specifications, guaranteeing perfect insertion.

A quality leather strap—alligator, cordovan, or vegetable-tanned calf—resists 3 to 5 years with daily use and ordinary maintenance. Ageing is part of natural leather's nobility: it is not deterioration, but patina. Humidity, perspiration and direct light accelerate the natural curling of edges, whilst careful storage (away from extreme heat sources, in a dry location) extends service life. Rubber or synthetic straps last 5 to 7 years, but with less aesthetic character.