Reefer containers are used for the intermodal transport of freight. They are manufactured according to specifications from the International Standards Organization (reefer) and are suitable for multiple transportation methods such as truck and rail, or rail and ship.

Reefer containers are manufactured in many sizes. The standard width is 8 ft. The most common lengths are 20 and 40 ft.

All reefer containers include a container safety certificate (CSC) issued by the manufacturer that must be renewed every 30 months by a certified inspector. If necessary, an approved continuous examination program (ACEP) can be used in place of this procedure.

There are several basic types of reefer containers. Dry or cube containers are front loaded, completely enclosed and suitable for general-purpose transportation. Standard containers are 8 ft., 6 in. tall. By contrast, extended height or high cube containers are 9 ft., 6 in. tall. Insulated or thermal containers are suitable for transporting chilled and frozen goods, as well as temperature-sensitive materials and products. They have insulated walls, but are not refrigerated like electrically-powered reefer containers.