A lead terminal includes signal lead pins and GND lead pins. The signal lead pin connects one signal pattern on a flexible substrate and another signal pattern on a rigid substrate. The GND lead pin connects one GND pattern on the flexible substrate and another GND pattern in the rigid substrate. A holding member has an insulating property and holds pairs of the signal lead pins and the GND lead pins at a distance. One main part of the signal lead pin and another main part of the GND lead pin form a microstrip line structure.