Santoni as you may know is a artisan leather company in Italy, noted for its very high-end quality and specializing in shoes. You can read about them at en.wikipedia.org/wiki/Santoni.
The new Portofino Handwound uses straps made especially and exclusively by Santoni --they've never made watch straps before. IWC talked them into it! And they really are terrific as this candid photo shows:

To my knowledge these straps will be used on certain Portofino models and no other IWC lines. When I said to one person in product management "these are special --people will want them to retrofit on their other models", the response was "we know". I then asked whether enough will be in inventory and the reply was "we've ordered a lot; we hope so".
Nice, really nice.
P.S. As before, this photo is exclusive here and for IWC. Please don't show it elsewhere or provide a direct link to it; thanks for your understanding.