Reefers (refrigerated containers) are a type of intermodal container equipped with a refrigeration unit to transport temperature-sensitive cargo such as fruits, vegetables, dairy products, chocolate, wine, pharmaceutical products and frozen meat. Although reefer containers come with an internal refrigeration unit, they run on an external power source, whether it is a power point on a ship or a power point at a terminal. When they are connected to the trucks that transport them, they are powered by diesel generators on these trailers, called "gen sets".