A circuit assembly is sealed in an outer casing (5) filled with a sealing compound (6). A terminal (4) for an external wiring connection to the circuit assembly is bent into an L shape with one leg provided outside of the casing and forming an external wiring connection portion (4a) and the other leg extending into the casing and connected to the circuit assembly. The wiring connection portion (4a) is superimposed on a terminal nut (7) provided in a recess (5a) on the casing top. An anchor portion (4c) bent downward is disposed at the free end of the external wiring connection portion (4a) the tip of the anchor portion being inserted into the casing (5), embedded in the sealing compound (6), and fixed there. By means of this construction the support strength of the wiring connection portion (4a) of the terminal (4) is improved. <IMAGE>
