Refrigerator car

Railroad car designed to carry perishable freight at specific temperatures

A refrigerator car is a refrigerated boxcar (U.S.), a piece of railroad rolling stock designed to carry perishable freight at specific temperatures. Refrigerator cars differ from simple insulated boxcars and ventilated boxcars, neither of which are fitted with cooling apparatus. Reefers can be ice-cooled, come equipped with any one of a variety of mechanical refrigeration systems, or use carbon dioxide or liquid nitrogen as a cooling agent. Milk cars may or may not include a cooling system, but are equipped with high-speed trucks and other modifications that allow them to travel with passenger trains.

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