PURPOSE: To facilitate shield connection of a signaling wire to be connected or inter-terminal connections for those to be given a common potential by mounting an aux. socket in the surrounding of an IC or an IC socket at the same time as its being mounted on a printed circuit board.

CONSTITUTION: Projecting terminals 2a-2j of an aux. socket 10 are arranged in the same direction as the terminals of an C concerned and connected electrically with the internal conductor 3 in the body. An IC socket 7 is accommodated in the bored off portion of this aux. socket 10, followed by mounting on a printed circuit board 6, and on the rear side of the printed circuit board 6, the ground terminal 9 of the IC socket 7 is connected with the mating projecting terminal 2j of the aux. socket 10. Thereby all other projecting terminals of the aux. socket 10 are put at the ground potential. To connect a shield wire with a terminal 8 of the IC socket 7, the external conductor of the shield wire shall merely be connected with the projecting terminal 2g of the aux. socket 10 nearest the terminal 8, so that connection of shield wire is facilitate.