To be capable of easily avoiding lengthening and heightening with a simple configuration even in a case where relatively large electric power is supplied.Provided is a configuration in which the conductor resistance of a plurality of contact members 13 and 14 is reduced in accordance with an increment in thickness and energization allowable electric power is increased by one of more of the contact members 13 and 14 being formed thicker than the rest so that an increase in the size of an electric connector such as lengthening and heightening is prevented even in a case where the supply electric power with respect to the electric connector is large and the retention of a flat plate-shaped signal transmission medium F is enhanced by contact portions of the thickness-increased contact members 13 and 14 being pressure-welded to the flat plate-shaped signal transmission medium F.