An inner terminal (54) of the present invention includes a horizontal part (C) held in an insulator part (55) covered with an outer terminal (56) and a suspending part (D) extended in a direction substantially orthogonal to the horizontal part (C) and having a lower end part connected to a signal patter of a circuit board. In the suspending piece (C) as a part opposed to one pair of side surface pieces (56b) suspended and extended in the outer terminal (56), plate shaped impedance adjusting pieces (54c) are integrally provided which respectively face the side surface pieces (56b) with prescribed spaces held from the side surface pieces.