Connection device using connector

A connection device comprising a plurality of electrical wires and a connector that is provided with a plurality of wire insertion holes receiving end portions of the electrical wires and terminal fittings connected to the end portions,

• wherein the plurality of electrical wires include a lead wire and a dummy wire that is the same in kind as the lead wire, such that one end of the lead wire is inserted in the wire insertion holes of the connector while another end of the lead wire is connected to another connector, such that one end and another end of the dummy wire are inserted in a pair of empty ones of the wire insertion holes of the connector, and such that the dummy wire includes a curved end portion which is curved in U shape and which is located on side of the other connector,
• wherein a tubular-shaped protective tube, which is shorter than the lead wire, is provided between the connector and the other connector, so as to extend over an entire length of the lead wire except opposite end portions of the lead wire and so as to cover the lead wire and the dummy wire, and
• wherein the curved end portion of the dummy wire is exposed from an end portion of the protective tube which is located on side of the other connector.