Strap for Portugieser Perpetual Calendar 44 White Gold / Dune

The lug width of the IWC Portugieser IW5037-04 is 22mm. This width is specific to this model and ensures harmonious proportions with the 44.4mm case diameter. To verify compatibility, measure the distance between the two lugs (the slots where the strap attaches) on the case: it must be exactly 22mm. An error of even one millimetre will compromise both aesthetics and comfort when wearing.

For the IW5037-04 in white gold, Mississippi alligator is the most refined choice, particularly in black or Havana brown tones, which create an elegant contrast with the precious metal. Shell cordovan is an excellent alternative for those seeking a patina that evolves over time towards coppery hues. Vegetable-tanned calf leather represents the most versatile and durable solution, especially for daily wear.

To change the strap, remove the watch from your wrist and use a spring bar removal tool. Insert the tool's tip into the small lateral cavities under the lugs and gently press to compress the internal spring. The strap will lift away, allowing you to extract it. During this operation, protect the watch crystal with a soft cloth. Install the new strap by reversing the procedure, ensuring the lugs seat perfectly in the case slots.

Yes, absolutely. Artisanally crafted aftermarket straps in exotic leather (alligator, shell cordovan) or vegetable-tanned calf are completely compatible with the IW5037-04, provided the lug width is exactly 22mm. Many collectors prefer bespoke custom straps because they allow personalisation of leather, colour, buckle and stitching thread according to personal style and dial design. The quality of an artisanal strap often surpasses that of factory straps in terms of leather quality and craftsmanship.

The lifespan of a leather strap depends on material type and frequency of use. High-quality alligator, worn regularly but not daily, lasts 4–6 years before replacement becomes necessary. Vegetable-tanned calf, thanks to its more robust structure, can last 5–8 years even with daily wear. Shell cordovan, though more delicate, can exceed 5 years if protected from excess moisture. Occasional use and proper storage (away from heat sources and humidity) significantly extend the life of any leather strap.