A reefer container has a refrigerated engine. The insulated container can have a cooling engine. A reefer is always an insulated container, but an insulated container does not necessarily have to be a reefer. An insulated container, also known as an insulated container or ex-reefer, is a refrigerated container in which the refrigeration machine has been replaced by a sandwich panel. Cold air gets into the refrigerated container by means of a blower motor. A refrigerated container is not a mega freezer. You set the desired temperature and load your temperature-sensitive goods.