Canada is contributing an essential component of the International Space Station, the Mobile Servicing System (MSS), which consists of three elements: the Space Station Remote Manipulator System (SSRMS), or manipulator arm, the Mobile Remote Servicer Base System (MBS), and the Special Purpose Dexterous Manipulator (SPDM). The MSS is built for the Canadian Space Agency (CSA) by the Canadian company SPAR Aerospace Limited. Photo: CSA