addition the inner peripheral surface is plated and the press fitting fastener hole 28 is connected to the printed wiring 26 formed on the first printed board 12 moreover the inner diameter measurement u03c6 of the press fitting fastener hole 28 is made smaller than the inner diameter measurement u03c6 u2032 of the other through holes 18 a however the inner diameter measurement u03c6 of the press fitting fastener hole 28 may also have an inner diameter measurement made smaller by making a diameter of a bore hole from a drill or the like when piercing the through holes 18 a in the first printed board 12 smaller than the through holes 18 a for example alternatively as in the present embodiment in a case where the press fitting fastener hole 28 is also used as a through hole the diameter of the bore hole is made equal to the through holes 18 a and a thickness measurement of the plating deposited on the inner circumferential surface is made thicker than the through holes 18 a thereby the inner diameter measurement u03c6 of the press fitting fastener hole 28 can also be made smaller or the like than the inner diameter measurement u03c6 u2032 of the through holes 18 a when done in this way the press fitting fastener hole 28 can also be bored with the same drill as the through holes 18 a without requiring changing of the drill in addition plating thickness is ensured and thus a risk of the plating peeling.