PURPOSE: To connect desired incoming and outgoing lines by connecting an incoming line, which is wired in parallel with a matrix board, to an outgoing line contact by a matrix pin.

CONSTITUTION: A slide contact part 26 of a matrix pin 22 is moved and fixed to correspond to an incoming line 16 desired to be connected. One of plural pin insertion parts, which corresponds to a desired outgoing line contact 19 of a matrix board 14 is selected, and the pin 22 is inserted to a pin incoming path from this pin insertion part, and a contact conductor part 25 in the front end of the pin 22 is brought into contact with the contact 19, and the contact part 26 is brought into contact with the desired incoming line 16, and the incoming line 16 and the outgoing line are connected. Since the incoming line 16 wired in parallel with the board 14 is connected to the contact 19 by the pin 22 in this manner, it is unnecessary to form the matrix lines corresponding to all incoming and outgoing lines. The matrix board doesn't require pin holes, and the matrix board is simplified, and the man-hour of processing is reduced and the device is miniaturized.