ISO intermodal containers are standardized steel boxes that transfer between ships, railcars, and trucks using the same standardized corner fittings without rehandling the cargo inside. They are not rail cars themselves but are the load units carried by well cars, flatcars, and spine cars. The ISO standard governs exterior dimensions, corner casting locations, and structural strength requirements. North American domestic containers (48 ft and 53 ft) are wider and taller than international ISO containers but use the same corner fitting concept.
Standard twenty-foot equivalent unit; the base unit of global container measurement used in port statistics and vessel planning.
Forty-foot equivalent unit; the dominant container size in transoceanic trade due to efficient stowage and forklift accessibility.
North American domestic standard for intermodal rail service; larger cube accommodates truck-equivalent loads on double-stack well cars.
9'6" exterior height (vs. 8'6" standard) for additional cubic capacity; prevalent in Asian imports and domestic retail distribution.
Integral refrigeration unit at one end; requires electrical power from ship, terminal, or rail car plug-in point to maintain temperature.
Intermodal containers enable seamless door-to-door freight movement by combining the long-haul efficiency of rail with the final-mile flexibility of trucking, and they underpin the global supply chain for retail and manufacturing.