A mechanical power communicating device and a modular system of a host and a mechanical power communicating device for communicating a mechanical power service. A first component of the mechanical power communicating device communicates a mechanical power service from host to a second component of the mechanical power communicating device or to a functional device. The mechanical power communicating device may be a functional device, an adapter for coupling a functional device to a host, or a functional unit of an adapter and a functional device. The mechanical power communicating device may include a first component having a first interface connectable to the host, the first component pivotally connected to a second component having a second interface connectable to the functional device. The modular system may include a host having differently oriented mechanical power service interfaces and the mechanical power communicating device.