A knee joint endoprosthesis system includes a femur component, two friction bearings and a tibia component. In one example, an access terminal may obtain a data message for transmission, and registration information associated with the access terminal. The shield plate includes a mounting flange having a boss for receiving a mounting fastener. The in-tower storage reservoirs could be defined by lower and upper water storage containers attached to the inner or outer surface of the tower that might be connected to other neighboring reservoir. The steel support structure may be a hollow, U-shaped steel tube having first and second attachment features at distal ends thereof for attachment to a lower seat structure. Arcing between screens is reduced by using a relatively resistive material for at least one of the screens exposed to arcing.