The XDCU-55 is another key component of Sony's Camera Extension System, consisting of camera adaptors, which connect to the camcorder, and a camera extension unit, which controls key camera parameters via one of Sonys remote controllers. The XDCA-55 docks to the PMW-350 and PMW-320 camcorders (sold separately) via an optional CBK-CE01 50-pin connector, and to the PMW-500 via the optional CBK-HD02 50-pin connector. Thanks to this mechanism, no other connection cables are required. The XDCA-55 connects to the XDCU-50 Camera Extension Unit via two BNC cables (not supplied), one for the camera signal, the other for the return signal. Additionally, a CCZ-A cable (sold separately up to 100m) is required from the XDCU-50 to supply power to the XDCA-55. The camera signal and return signal can be transferred up to 100 meters (328 feet) without degradation. The system offers an affordable solution for situations that require maximum versatility of each camcorder in either stand-alone or multi-camera operation.