The Carnet de Passage en Douane concerns the temporary importation of the vehicle itself, not the goods.
The source states that European countries generally allow temporary importation of foreign goods vehicles free of duty/deposit without guaranteed customs documents.
Some Middle Eastern countries may require a Carnet de Passage, depending on the time the vehicle remains in the country.
Carnets de Passage are issued by AIT/FIA (Alliance Internationale de Tourisme / Fédération Internationale de l'Automobile).
The source states they are normally valid for 12 months.
This Carnet applies solely to the vehicle and not to the goods.