USOS(The US Orbital Segment (USOS) is the name given to the components of the International Space Station (ISS) constructed and operated by the United States National Aeronautics and Space Administration (NASA), European Space Agency (ESA), Canadian Space Agency (CSA) and Japan Aerospace Exploration Agency (JAXA). The segment currently consists of eleven pressurized components and various external elements, all of which were delivered by the Space Shuttle.
wikipedia.org)
