A Carnet is an international import-export document. There are two different types of Carnets, but the one that is most commonly used is the Carnet ATA. This document is used for a variety of different goods, but has some goods that cannot be shipped with it.
A Carnet is needed when you are trying to import or export certain goods from certain countries. If you are trying to import or expert professional equipment, goods for a fair or exhibition or commercial samples, you will need to get this type of document. The Carnet you need will depend on which countries the goods will be coming from, going through and going to.
However, a Carnet ATA is not acceptable when you are shipping consumable items. This can include a wide variety of goods, such as agricultural items. You cannot ship explosives with this type of document either. You also do not need a Carnet when you are using postal traffic.
Understanding what type of shipping documents you need is important, but it can be a challenge for people who are new to this type of work. Make sure that you do some research about different Carnet. Talk with an expert in order to make sure that you understand the application process, when you need a Carnet and which countries accept them.