A one-piece, molded, terminal cover providing a weatherproof enclosure externally of a field-mounted component is disclosed. A first member has a back face adapted for external connection to the field-mounted component. The back face has at least one opening communicating with an opening in the field-mounted component through which outgoing wires extend. The back face further has a continuous, external rib around the opening for providing a gasket. The first member additionally has a top face, a bottom face and two side faces. A second member has a front face, a top face, a bottom face and two side faces. The bottom face has at least one opening through which incoming wires extend. The first and second members are flexibly hinged and cooperate when in the closed position to define the weatherproof enclosure wherein the incoming and outgoing wires are connectable. Means are provided for locking the first and second members in the closed position.