A Pump has several Ports. While most Pumps have inlet and outlet Ports, the number of other Ports may vary. For this reason, the concept of Ports is introduced. Ports can be used to connect other components or systems to the Pump. In this specification, the input and output Ports, as well as the drive Port for the connection of the pump drive are defined. A port is not part of a submodel and therefore a port is modeled as a separate BaseObject and not, like submodels, as a FunctionalGroup. Figure 8 shows how the Port concept was integrated into this OPC UA Companion Specification.