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Swap bodies take advantage of the large number of trailers used to carry standard ISO containers. The design of swap bodies and roller container is optimized to minimize empty weight, saving on trucking fuel cost (less dead weight to be transported).and cost of built of reloading terminals. 
As a consequence, swap bodies do not have upper corner fittings, are not stackable, and must be lifted by the bottom frame, unlike the more widespread shipping containers (ISO containers). This makes them unsuitable for ship-based overseas transportation. Because they are not stackable and are lifted by the bottom corners, they require special handling when transported by rail. Due to security concerns, an increasing number of swap bodies have a hard surface instead of curtains and tarpaulins.
Swap bodies are typically more expensive than equivalent payload ISO containers. This is because the ISO containers used in Europe are typically manufactured in China, whereas swap bodies are made in Europe (central Europe and the UK). The lighter weight of the body offsets this cost in fuel savings during transport and increased cargo capacity.
Swap bodies normally have the same external dimensions for the bottom corner fittings as ISO shipping containers, so that they can be placed on the same kinds of trucks, trailers and railroad cars designed for shipping containers. However, to optimize the carriage of pallets, wide bodies are often scaled to the maximum width allowed for standard road trucks and railroad cars and to a different length accommodating a quantity of European-pool pallets (0.8 m × 1.2 m or 31.5 in × 47.2 in) without leaving empty space.
Many swap bodies are fitted with four up-folding legs under their frame. These legs make it possible to change, or swap, their body from one carriage to another, or to leave the swap body at a destination, without using extra equipment such as a crane or hoist.
Special swap bodies may have more doors or sliding panels than ordinary hard boxes for trucks, railroad cars, or sea containers. This feature makes unloading and loading faster and easier.
Many swap bodies are fitted with keyhole tracks. These secure a range of extras such as shoring bars and cargo nets to extend its uses in various applications. Recently a second flooring using folding shelves has been used to aid postal companies.
All swap bodies are subject to extensive non-destructive (in most cases) testing, some in-house others not, regulated by certifying authorities.
Basic standardization is set with Euronorms EN 283, EN 284 and EN 452 for construction and design, as well as EN 13044 for marking and identification. The panel responsible for developing standards is CEN/TC 119. The outcome of this panel has not yet provided any contribution to automation, as handling the swap bodies is a traditional haulage business with truck drivers involved.
- "Das Logistik-Glossar" [The Logistics Glossary]. DHL Logbook. DHL. 2008.
- Lewandowski, Krzysztof (2006). "Swap bodies without reloading terminals in rail transport system" (PDF). Technika Transportu Szynowego. 6 (12): 53–55. ISSN 1232-3829.
- ICF Consulting Ltd. (13 October 2003), Economic Analysis of Proposed Standardisation and Harmonisation Requirements, Final Report (PDF), The European Commission, archived from the original (PDF) on 11 October 2010
- "Swap bodies". DFDS Logistics. 2014.