4.8mm thick in 24 and 26mm using Italian Old Military Vintage Pouch Strap leather.  You will not find an Ammo Pouch strap as soft as this.

His family made the original straps for Panerai in 1938 in their shop.  Now the same artisanal touch is in every strap from the Fabrizio Ciampi collection.

Hand made in Castelfiorentino, Italy just outside of Florence, the Cuoierie Mecchaniche Brelli is known for their quality leathers and workmanship.