Circuit members and electrical parts, connected to the circuit members, are mounted within a pair of division housings and terminals, extending from the circuit members, project outwardly from the division housings, and the two division housings are joined together to form a connector. Walls of the pair of division housings are alternately superposed together. An opening is formed in an outer wall of each of the two division housings, and the circuit members are exposed through the opening. The electrical parts, mounted within the two division housings, are arranged alternately. The pair of division housings, jointed together, are received within a case, and the case has a hood portion for the connector.