A reefer container (short for "refrigerated container") is a special type of container used for transporting perishable goods that require a controlled temperature. These containers can be refrigerated, heated or kept at a constant temperature, depending on the requirements of the goods they carry. Reefer containers are used in shipping, road transport and air cargo to ensure products remain in the right conditions during long shipments.

Functions of a reefer container:

- Temperature control: Reefer containers can usually maintain temperatures from -30°C to +30°C. This makes it possible to transport both frozen and refrigerated goods.

- Air circulation: These containers have systems to regulate airflow, so that cool air circulates throughout the container and goods are cooled or heated evenly.

- Humidity control: Some reefer containers can also regulate humidity to maintain cargo quality.

Examples of goods that can be transported in a working reefer container:

Food products:

- Frozen foods: Meat, fish, poultry and frozen vegetables.

- Fresh produce: Fruits, vegetables, dairy products and flowers to be kept at a cooler but not frozen temperature.

- Ready-made meals: These need to stay fresh or be kept at a certain temperature.

Pharmaceuticals:

- Vaccines, medicines and other pharmaceutical products that are temperature-sensitive.

Other perishable goods:

- Chemicals: Some chemicals and industrial products also need temperature control.

In short, a reefer container is essential for the safe transportation of temperature-sensitive products over long distances, where accurate temperature control is crucial for maintaining the quality of the goods.